I've seen this before, but figured I'd share it :)

I've always thought the 4.9 would be an awesome engine for this application due to it's power and torque curve as well as overall weight/size. What a cool truck to put it in aswell :) Neat pictures and goodies in there for ya. If it'll fit in a Trooper, then it'll fit in an Amigo ;)... ah well I'm keeping it simple and going for another 2.6. For reference, the Troopers could be had with the optional Chevy 2.8 V6, which produced only 5hp more, but the same torque as Isuzu 2.6 I4 (tho the 2.6 has a lower/better torque curve) which in turn tho, they share bolt patterns, and the 2.8 shares bolt pattern with 4.x series engines. Same goes for the early Rodeo's with the 3.1 Chevy V6, but on top of all that... it's a manual too :)

http://myweb.cableone.net/bcanderson/trooper/Cadillac/cadillac.htm

Note how he has used a 4.5 liter intake manifold to fit the TB...