Not that I am aware of. I built two 351C's several years ago, both leaked. I thought it was the rear main, but I took my 72 apart (dropped pan) and immediately knew the pan gasket popped inside during tightening. One fixed! The other on my '69 Mach - I bought a new pan gasket for but haven't had time to take apart. I wondered about and looked for a one piece gasket, but could not find one for the 351C. Getting a leak free install is possible, but given my track record I am going to shut up now! ;-)