Yea I think mine is gen2, so in the thread you posted, are a lot of the parts applicable for both models? The thread you linked in gen 2.5
Yes, Interior is directly the same, drivetrain is 99% the same. Gen 2's came with a few different flavors of engines, including SOHC and DOHC versions. The parts for the 3.0 SOHC are mostly the same as the 3.5 SOHC motor, with minor exceptions to the "front plate" the that holds all the accessory items on. The DOHC is pretty different however. You'll often find the motor referenced by its code name, and I can't for the life of remember it right now, I think its something like "6G72" or 74 or something like that. They used the same engine in several vehicles and across model years, though it grew from 3.0 to 3.5 to 3.8, all on the same basic engine design.
The Gen 2.5's I think were all 3.5's from 98-2000, and then the Gen 3's were initially 3.5's until 2003? and then went to 3.8L versions. All very similar