Restoring a 1968 Datsun 510 Sedan – Part 8

We’re back!

Distractions abound… The 240Z has developed a fuel delivery issue, the Roadster needed a complete wiring harness replaced, which turned into a full dash and gauge restoration… The daily drivers needed maintenance, and some of the 510 parts we were awaiting took FOREVER to arrive.

Let’s pick up where we left off. The wiring was all run to the proper places, and I wanted to make sure everything electrical will work before I start putting the interior back together. So, after a day in the garage with a battery hooked up temporarily, a multi-meter, and a copy of the “new and improved” wiring diagram, we have confirmation: Everything works! Couldn’t resist clicking over the ignition, just to check the start circuit. Sure enough, the engine turned over, so I think we’re good to start reassembling the interior!

The stock 510 seats had been refurbished by the prior owner. However, they sit far too high in the car for my taste, and they offer zero lateral support. I intend this car to handle quite crisply, so I don’t want to feel like I’m sitting on a bar stool when it does. Racing seats always seem “cheesy” in a street car, unless it sees track time, so those won’t work either. Basically, I wanted something period-correct, that looks like it *could* have been originally offered, with a lower pan, better bolstering, and a safer seatback design. There’s a real good choice out there: BMW E30 bucket seats.

Now, the E30 seats were offered in two designs: Sport and Comfort. The Sport seats are very handsome, but are hard to come by – and they look a little out of place in a ’68 car. But the Comfort seats have a nice balance of old-school flavor and good supportive bolstering, plus they have a cool waffle-pattern in the center that looks very 60’s-70’s. Since the interior already feels like a tomb with all the black carpet, dash and vinyl, I wanted something that would lighten up the look a little – the tan E30 Comfort seats fit the bill perfectly.

Click on the pics for a better view…

Of course, the original 510 seat risers have to go, and there’s the added challenge of working with the floor brace (which runs from the side sill to the trans tunnel). It’s about 3″ tall, and sits almost exactly where you’ll want the front of the seats. Fortunately, I’m 6’1″, so I don’t mind the seats being mounted fairly far back. This presented an issue with the seat slider adjustment lever, which juts out directly to the front of the seat pan. Nothing is insurmountable, and BMW designed these seats nicely – The mechanism for adjusting the seats can be relocated, so I removed the front-mounted lever and will attach a lever on the side of the seat to accomplish the same goal.

Naturally none of the mounting holes will line up properly – This is where it pays to be patient. Setting the seats in the desired position, measuring the “squareness” of the seats, marking the mounting holes and drilling them out is a pain – but once completed, you’ll be glad you took your time. NOTE: The 510 floor pan slopes away from the center tunnel, so you’ll need to add about an inch of spacer to the outboard bolts. I used a stack of washers to get the desired height for testing. Once they’re installed, check for “squareness” again by setting both seatbacks to the upright position and view the seats from the front and rear of the car. You’ll notice if there’s any “tilt” and can adjust accordingly. Once I had my spacer measurements, I removed the stack of washers and cut a piece of round aluminum stock to that height, drilled the center out for the seat mounting bolt, and reinstalled it. ALSO, if you’re using this method, use self-locking nuts (I used new stainless Nylock nuts) and use a thick, LARGE-diameter washer on the underside (for safety in the event of an accident). This process took the better part of a whole day, so be patient!

I bought the rear seat from the E30 donor car as well, on the off-chance that it *might* fit with some persuading… Close, but no cigar. So, the rear seat from the E30 and the original 510 rear seat have been dropped off at my upholstery shop to have the E30 covers modified to fit the 510 seat cushions. This way, they’ll match the front seats perfectly and still fit the 510 interior.

In the meantime, I reassembled the dash… with the new wiring in place, there’s a lot less spaghetti under there to deal with, and it gave me an opportunity to replace all the light bulbs and clean the gauges and lubricate the switches. I picked up a set of brand-new pedal pads at a swap meet for $1, and those look great on the pedals:

While waiting for the new radiator to arrive, I took this time to install some sound deadening in the doors prior to replacing the door panels. As with all my other restorations, I used GTmat. A little goes a long way, but unfortunately, I forgot to take pictures of the rest of that part of the job. At any rate, roll down the windows, clean the inside of the door shell with some degreaser (I like the orange stuff), and apply the sound deadening firmly. After making sure it’s adhered fully with the roller, I like to “warm up” the application area with a heat gun – just enough to soften the adhesive and give it a good permanent bond.

Well, the radiator still hasn’t arrived. Remember in Part 7, where I was trying out something different for the door weatherstrip? Well, I pulled that off and replaced it with new “stock” weatherstrip – much better. The doors close firmly (and quietly, thanks to the fresh window squeegies, the GTmat sound deadening, and the new rubber). So, now I can use my door sill plates!

Big problem – They look like crap. 40 years of abuse on a door sill means the thin aluminum plates are bent, dinged, scraped, gouged, and filthy. Some people would throw them away and go without, OR they’d make new ones. Neither is an option – Going without means you’re tearing up your door sill paint getting in and out of the car; and homemade door sill plates never wind up looking “correct”. This isn’t a Cavalier with a Combat body kit, so we’ll try to rehab the original door sills.

Here’s how they looked before:

I decided to try bead blasting them. At least that way, I could get a good look at the condition without destroying the metal, and I’d be able to see if they’re salvageable. As it turns out, I think I can rehab them. Here’s how they look after bead blasting:

Not bad. If I can’t work the metal totally smooth (which is unlikely), I think they’ll make a real good candidate for a coat of bedliner material. It should conceal the minor dings and provide good protection to the door sills.

UPS just rolled up with a box shaped remarkably like… a radiator! Break time, and we’ll be back with the next episode.

Click here to read Part 9 of the 510 build!