did they pull the flywheel off, perhaps too change the rear engine seal? it's normal to do that when the trans is out. what could happen is the flywheel can be disassembled, then reassembled wrong. don't know if it will run as i think it wouldn't start that way. btw, the flywheel can come off in 1 piece, also. i just know people who, for some reason, take it apart and had problems with the car . good luck, chuck.