Both gens bolt up the same, it'll have a 15mm nut on the upper starter stud (tranny side) holding the wiring harness clip. Once you remove the nut and clip, you can take both 13mm studs off. The gen1 cars have a 10mm bolt that holds a bracket to the block, and also have the hot feed coming from the solenoid on the fender, 10mm I think. The gen2 cars have the solenoid on the starter itself, and the connections are easier to get off/on. Also the gen2 starter is smaller and easier to wiggle out.
mark
89 SHO (getting a lighter gen2 stater)
92 SHO
93 beater