I think the 700R4 transmissions out of S10 vehicles have a different bolt pattern than that of a 350 engine bolt pattern. The S10 700R4 transmission has two bolt holes in line with each other across the top. It doesn't come to that peak at the top, it's flat.

I found a picture of one on Ebay...

 

it sould have a big letter K on the top of bell housing

 

thanks guys.

here are some pics of the tranny:

and I found this:

 

look here
http://www.purplesagetradingpost.com/sumner/techinfo/700R4p1.html

 

thanks for the link.

i saw it some time ago, but forgot about it....

 

If you get one out of a 4.3L S10 you will be ok. people say that 700R4's only last 80-100,000 miles but My old S10 had 215,000 original miles on the 700R4.

 

cool. the problem is that the guy I'm getting it from *thinks* it was from an s-10...