I am in the process of planning my t5 conversion. The car is a 1969 Mustang Coupe with 302 and C4. I am swapping to a 1990 T5 BW WC tranny, i am also going to use the late model T5 bellhousing.

My question is regarding the slip yoke needed for this conversion. I know that many conversion kits come with a shortened slip yoke to compensate for the longer T5 but my question is if i can modify the existing slip yoke for the C4 to work with the T5. I have access to a machine shop so would i be able to put the C4 Slip yoke on a lathe and take off the 3/4-1" needed for the install. Would the spline on the C4 slip yoke go deep enough to let this work?

Thanks for the help