http://www.v8s10s.com/id3.html
i dont want to post all this guys pics, but he has put a lot of LS1's in first gens.
it is no harder than an LT1 in an S10. all you need is either to notch the frame for the a/c compressor or a bracket from Street and Performance to move the A/C to the top of the motor and vette alternator brackets to clear the steering box
Jags that Run have headers and motor mounts, cooling isnt that big a deal, you can use a 92-96vette radiator that has a built in oil cooler for an auto tranny...
biggest thing is the electrical, but Current Performance Wiring will get all you need for the LS1