v8 and v6 conversions have been done. the guys on here mostly have the first gen body style trucks though so you have to improvise off what they have done. I have heard that the swap info is the same. I know the suspension part of the truck is the same between the two body styles.
it seems to me someone over there or here did a s10 frame swap, maybe it was a blazer frame swap. But if you cant handle making a set of motor mounts for a v6 or v8 you're not going to want to do a frame swap like this as it is deffinatly not bolt on. Going to be a bit of fabrication involved to get it to work.
You might have better luck over at this forum as it is for us 2nd genners:
http://www.isuzupup.com/forum/index.php