I have a 351W on my 67 mustang. It currently has an FMX transmission. After I am done swapping several engine components, I plan on addressing my transmission. It currently gives me no power whatsoever in reverse, although when in drive it works fine. I've been told this could be because it needs to be rebuilt, or it could just need trans fluid. Does anyone have any other ideas?

Also, do you feel its better to keep the FMX or go with say a C6, or maybe even converting it to a stick?

Thanks for your help

 

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