Hello Dave,
Whoa! Seven inches is not a good number for that area
I would say you'd need twice that for a reasonable fit.
Maybe someone else can chime in here with some actual experience?
There is a shorter tailshaft and housing available for the C6. I believe they came in 4WD vehicles such as the full sized Bronco.
Or you could move the engine forward a bit (I knew you didn't want me to say that
).
Do you have any photos to post yet?
Regards,
Tom
PS: By electing to construct a Cobra replica, you are automatically enrolled in the WDGUE club