Are you sure you don't have a chevy A833 OD (NP440) trans? I believe it had the old saginaw bolt pattern but could be wrong. Here's a little more info:

http://www.jalopyjournal.com/forum/threads/np-a833-trans-question.697901/

Yep....I don't think the bell is off...it looks like it matches a BigBlock one I have. I think the hole in the trans if off a little.

you could be right therocks....I'll look at that again.

Did you take measurements of holes between the 2 ?

Do you have another trans case , or another bell ? either way take measurements between the 2 of whatever you have .

In researching this...I think you figured it out! The saginaw and 833 bolt pattern is almost the same with just that one bolt hole being slightly different. So I have a chevy version of the 833....but it will still work, I'll just slot that hole and I should be good to go. Thanks! Makes me feel better knowing why....

I actually do have another trans case (empty) and another bell...I'll measure both just to document the difference. If you see my post above...I think Blown340 got it right...I think it's a GM version of the 833 with the saginaw bolt pattern. I actually have an empty cast iron '75 833 O.D. mopar trans case here that I bought awhile back to swap these internals into to beef up the O.D. a little.

I just thought of something....if it's a chevy version...does it have the same input shaft as a mopar trans? That could be a problem.....

When I get home...I'll have to count the splines. This article says the GM 833's had 10 spline input shafts.

Hemmings 833 article

I went back and looked at my pictures...no way that's a 10 spline input shaft.

I believe the output splines would be different as well if it's a Chevy.

Rob , in case you haven't figured it out those are the trans bolts there on the inside , I just put them there so I could set it on the shelf trans mount side down .

Good to see you figured it out , which hole was it that was off ?

I want to say the truck I got that out of was an 87 ... but I remember it having the 1991 up grille in it ???

I don't know if they were using a hyd clutch in 1983?

that's not a 10 spline , but if it were no biggie , the clutch disc won't care what it's behind , check the driveshaft end though ...

I think I have an output shaft if you need it .

Yep...I found the bolts...I appreciate that. It was the passenger side bottom bolt hole on the trans that was off. In my original post I said Drivers side..but I was mistaken.

I'm not sure when the hyd clutch first appeared...I find conflicting info on that.

Good point about the splines....I worried about the input shaft length though...but I think it's good...I'll check the output splines when I get home. It does have a mopar tailhousing though...so I should be good.

Input shafts are different lengths also. I have both in the garage and the GM is about an inch shorter.

Yep, that is one reason they cut the input shaft down to run 833's in Chivvy's, the other reason is they need to use a roller bearing in the crank instead of a bushing.

Wow....learned something new every day.

Almost two years later too

LOL....third generation don't care.