Hi,
I'm a bit rusty on the foxbody stuff,So please forgive me. I just wanted to give you a heads up.If your engine is the stock original one from 1986,It has unique one year only Heads and Pistons,Which make swapping to aftermarket heads all most impossible without changing pistons as well.You should double check with the head manufacturers? Back when I used to play with Fox bodies alot,I always remember the ads for heads would have an asterick which said not for use on 1986's due to piston clearance issues.