Currently, I have a '70 Malibu that will have a TH 400 and a 10-bolt stock rear-end . The rear is orig and has never been out of the car. The trans is new and has never been in the car. Everything will sit behind a 454...

I recently acquired a driveshaft from 7DSS (Chad) here on TC that I believe was from a '70 TH350 'velle, but not entirely certain - the yoke was definitely NOT designed for a '400.

Anyway, I can measure the length of the drive shaft, and presuming it comes in around 55-1/2" or so, I figure it should work - right? I've pounded out the yoke, cleaned the shaft up and will be getting it powder coated and then will put a new th400 yoke on it.

I want to make sure that it will work with the TH400 and the rear-end, but without the trans in place (going to be awhile) I don't know what measurement I'm looking for to be certain that this shaft will fit.... Is there a range that it should be in to expect it'll work on a fairly "stock" configuration? Are there particular u-joints I should look to use? The old one's are pretty toast, so I'll be putting new ones in - especially if I have the thing out anyway...

Don't know that photos of the shaft matter, but here they are from Chad's showroom:

http://www.chevelles.com/showroom/sh...8/limit/recent (http://www.chevelles.com/showroom/showphoto.php/photo/6958/limit/recent)

http://www.chevelles.com/showroom/sh...7/limit/recent (http://www.chevelles.com/showroom/showphoto.php/photo/6957/limit/recent)

http://www.chevelles.com/showroom/sh...6/limit/recent

I have it all wirebrushed down to clean metal and both U-joints and the yoke are removed. Anything in particular I should look for prior to investing in the powdercoat work? I need to get it done soon as the guy who owns the shop is on a time crunch and is giving me a great deal
to do several parts.

Thanks for any input you can offer!

If you need to get it cut the shop will install new ones for you. If you dont, OEM replacements will work fine. The only way you can be sure if it will be the correct length is to insall the tranny, and measure from the seal surface (on the tail shaft) to the center of where the rear u-joint will be installed (the surface of the pinion where the u bots go through).

How tight do the tolerances need to be? I could probably measure the trans length, then measure from the block to the rear end and subtract out the trans length.

It wouldn't be exact, but I can probably get it within 1/2". Does the yoke wind up going all the way into the tail or does it only go in part-way?

Main thing is I want to take advantage of the powder work, but I don't want to do it on the wrong shaft!

That would work, but you need to support the tapemeasure so that you dont have any sag. And within 1/2" you will be fine. The yoke will not go all the way in when at rest, it is made so that with the flex of the rear axle it will allow enough room for it to move in and out safely.