Yikes. That is some pretty high mileage on the motor to even think about putting a blower to it. The GT-40 long block is a nice budget-minded motor when the time comes.

I had an '87 5.0l with the AOD. It was great when the AOD functioned properly (usually right after the twice a year rebuild). If I could do it all over again, I would have swapped to a TKO or 3550. The AOD is such a piece of shit transmission. But if you are dead set on keeping an auto, go with the C-4. Then again, my views with the AOD are pretty jaded so you probably shouldn't listen to me.

My fuel guage had the same problem, as do many Fox bodies. Easiest thing is to swap it out for a newer cluster. This will give you a functioning fuel guage and a speedo that goes over 85mph.

Good luck with the project.