Hi, I'm currently installing a C4 on my 1967 mustang with an inline 6. It was originally a manual so I've had to collect all the parts for the conversion. Now that I have everything I began to install the transmission and the bellhousing, which is supposed to be for my car and engine (from a mustang retoration place), is not mating with the engine block properly. I can get all the bolt holes lined up correctly, no problems, but there is a guide pin on the driver side rear of the block that seems to be off by about 1/2 inch. Can anyone tell me what the issue is? Is this guide pin really necessary or could I cut it off and grind down the spot? Really need to get this fixed ASAP as this is my daily driver!