My parts came in from the US so I start putting things back together again, in the tranny. (Shifter rod o'ring, and shift fork pads)

I had it in neutral, as per the manual, for reassembly, but after getting the mid cover back in position, I am trying to slide the rear cover(extension housing) on, while pushing down on the détente spring/ball under the gearshift offset lever, and the shift rod moves. Now its in gear, and the rear cover won't slide down all the way, good till the last 3/4" only. I try again, and again..nope. I can't move the shift rod manually to get it back into neutral again, it seemed frozen.

So I have to pull the mid cover off again, (least the RTV hadn't fully cured) and slide the synchro and gear back into the neutral position. To test it all, I decided not to put the RTV on for now, so I put the mid cover back on with just a couple of bolts, and try sliding the rear cover into position. Dang thing still wont seat all the way down. It seems like something, perhaps from the reverse/5th gear shift rail is holding things up.

I can't seem to move anything manually to give me the needed clearance. I took the mid cover off again, and tryed manually moving the reverse gearshift lever.. won't budge. The only thing that seems odd, after peering in with a flashlight, is the reverse idler gear shaft has a portion of the roll pin sticking out. Now I never disassembled the tranny, and it seemed to shift fine before, through all gears. These roll pins are usually in pretty darn tight, and I can't see how my doing the little that I did, could shift it outward... Maybe it's supposed to stick out slightly..I don't know.? The case looks like it almost has a cut out to allow for this, so I wondered if it was supposed to be like that...

So any experts out there that can offer some advice. Should a portion of that roll pin be exposed for some reason? Why won't the reverse gearshift lever budge? I'm baffled..