I recently replaced my 5.0L with a 347 stroker in my 1991 GT. The engine description from the builder is:
Stock block, 0.030 over, SRP Pistons, Scat Rods and Crank
about 9.5:1 compression, balanced,SFI Damper
Patriot Aluminum 185cc heads with a little port work, Roller rockers, 280 HR comp...