I have run into a problem recently. When I bought my T-18 it had been slightly scavenged. It was missing the shifter and so ky question is are all the top covers of T-18 interchangable because I can't find a tranny with the shifter and then a screw on cover to hold it in all I can find are ones that the shifter is held in with a pin. I'm sorry if that is confusing but thanks for your help in advance.