Ok I may know a lil somethin when it comes to building a car, but not one thing on a manual trans. I have a 98 z24, honestly i'm not sure how to tell which trans is in it, based on parts for it, it's the izuzu. first one my spider gears stripped so I had to replace that($350 for parts set, off GMPP, and $60 for bearings from an aftermarket company), the gears-main gears-looked almost new, i mean literally looked new. I got it fixed put the trans back in, then the clutch stopped working, well didn't work, but it did before the trans came out. The hydraulic part seems to be functioning, yes i bled it, the pedal feels just like my 95 does, you can feel the release bearing make the pedal get tight and then soften up. when the car is moving you can press the clutch and rev the motor up, but it will not fall to idle, just rev matches(o yeah you have to start it in gear, even with the clutch pressed the car is in gear). well....now the car is seems to be stuck in second i think, based on rpm and speed. I can move the shift lever to the right, but not the left, I cannot put it into any gears, only reverse, but in reverse the trans grinds when you release the brake and the car still goes forward anyway. I am thinking one of the 3 shifting forks is bent or stuck, specifically the one for first and second, the clutch idk maybe the pressure plate or disk, or release bearing, or all are bad

That really sounds like a shift cable problem, or even the shifter itself. I would start with the shift cables though. Make sure that they are attached correctly on BOTH ends. And when you have the center console out, check the shifter out. If everything looks okay, I would take a stab at replacing the cables if they look the least bit worn. The fact that you can only move the shifter in some directions makes me think that it is not the shift forks. A final possibility is the shift control box. That is the piece that links the cables to the shift forks (it is the box that sits on top of the trans where the cables connect to). Take that off (I think it is 6 bolts) and inspect it for any slop or cracks. If none of that works, it is probably the shift forks.