I've got the motorcraft EV-127; T-Bird TC/Mustang SVO PCV valve. It seals against everything my lungs have to offer, so I think it's my best bet.

I'll be installing it and running around without my cat-back for today. I hope this solves my issues

On a second note, what would you guys flush an oil soaked exhaust system with? I'm thinking of getting 4 gallons of some bio-friendly degreaser from the auto parts store, cap the system off and top it off with water. Then I'll let it sit in the sun for a day or two and flush totally out. What do you all think, bad idea? There is a s$&% load of oil in it and I don't want to leave a massive cloud behind me as I drive any longer than I have to

2005 Ford F150 SuperCab FX4 1964 Chevrolet Impala SS 1998 CSVT: 354HP/328TQ @ 10 psi, now gone