Its not just the heads, but also the intake manifold, and a long list of other parts totaling like $1400. I already have the intake manifold and gaskets sitting in my garage. The install at Ford runs like $1000 too, but it includes a warranty.
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T-Bones '96GT
'96 GT 5-speed
Roush Cold Air Kit w/ K&N, 80MM Mass Air, Mac Cat-Back, Mac Pro Chamber H-Pipe, FMS 3.73's, FMS 70MM TB, March U/D Pulleys.