Now that I've gotten the motor running in my 68 mustang, I think the trans is shot, I tried all the gears and the car didn't move. how hard are autos, to rebuild? I have never tried one before, I mean I can remove a trans and replace it but never opened one up before. how do I know what type it is to begin with? also what years can I get a trans that will bolt right up with not alot of extra stuff needed, its a 3 speed automatic by the way. Thanks alot guys..