Stroked0347

Can anyone please help me out? I recently did a convertion from a 4cyl. Automatic to an 8cyl. 5 speed. Everything is ok, accept for when I put it into gear. The neutral safty switch doesn't work either. The 2 plugs are there at the top by the clutch pedal inside the car and I plugged them in and when I pressed the clutch nothing happened. I had to plug in the jumper plug again and she started. And the other problem is whats really bothering me. Whenever I put the car in gear, any gear 2nd or 5th or reverse the idle drops to where she almost stalls and then jumps back up. So is there something that I missed doing or need to do because it was an automatic and it's dropping in idle because it thinks it still an automatic. The car has a 93 8cyl computer and computer harness. I hope I don't have to change the main harness because I really don't want to ripe the car apart again. So any direction somebody can send me in is greatly appreciated. Thanks