Look here for "got some new stuff for engine R&R" it's about 8-9 pages back now.
I'm making 280whp on a mustang dyno with the old short block. I paid about $2100 for the new ej257 and gasket set.
174,000+ miles, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. Also CHECK YOUR OIL, these cars use it.