Turbo on a Fox is going to require some crazy fab skills just because of the placement of the exhaust manifold on the longitudinal engines. All the turbo manifolds for 8v's that I know of are for the transverse engines. You'll almost definitely have to have something custom fabricated.

The iron manifold in picture #3 looks like its from a turbo diesel engine. It will work on a transverse 8v but porbably not in a longitudinal engine bay because of the placement of the motor mounts. With that manifold you can only use the tiny turbo that came with the TD's so you're very limited as far as how much boost it will produce.