Slant 6 in Buffalo NY Junkyard
grew up in Northern MN and live in MI, I know all about salt & corrosion...
this stuff can work small miracles:
Blaster 11 oz. PB Penetrating Oil 16-PB-DS - The Home Depot
conversely, all you need to do is snap the studs holding the intake and exhaust manifold off and sawzall the headpipe and it's out in 5 minutes ;)