anyone know the stock piston ring sizes??

I'm trying to order just new rings, I can't find out what size the stock pistons take. I asked ford, they don't know,Summit, don't know, some racing shops, don't know, I'm ready to just get pistons and rings just so i know I got the right size! And of course i know 4.000 but the thickness of the rings is the ???? thanks

oh yeah, and I was told the stock 1988 pistons are forged is that true? If it is I'm shocked..

i give up.. after looking again, the only size I can find is.4.00 in. bore, 1.5 mm top/second rings, 4mm oil control ring, which on federal mogul makes. Looks like I'm going to have to rebuild completly.... great....