My Gen II FSM has no diagram either. (I need to get better ones!) I would think that they are fundamentally the same as the Gen I, Active-Track aside. Yes to their going in on the front. I think the only gears in the rear, with the chain, are the ones that engage the 4WD. The hi/lo are in the front.

In the gear/shaft/fit comment I first made, when the guts are taken out, if the case is front side down, the chain, it's gears, and the two shafts can all be pulled up and out from the case. But when the new gears are on, the whole thing won't (might not) go back in the same way. One of the new gears is slightly larger than the hole that they came out through.

What needs to be done instead is to assemble the chain, shafts, etc., and slide them back in while fitting the gears on in the process from the other side of the hole. at the end of it all is the snap ring that the only way to get it back on is with pliers that have been ground thin enough to fit in what little space is left.

Whoa, was just looking though some old pics... DON'T FORGET TO SHAVE THE SHIFT FORK that sits above the new gear. You should see a small grinding that is there from its fitment to the old gear. You may have to take a little more off. Be sure to test the shifting before calling the work done.

I added pics at the end of my old thread.

HTH

P.S. Interesting comment from Kevin on needing to index the gears. I don't remember that being the case with me. But mine was MT, so maybe there's something different there. We know the gears are different in some way.