I have had exactly the same experience as Jack 21, down to the fitment issue with the windage tray. It can be leak-free as he describes.
The four piece gasket is the only option, as the front and rear portions of the Canton pan mounting flange have a raised bead that is incompatible with the similar raised bead on the one-piece gaskets. Why Canton doesn't offer a beadless flange version I don't know.
If you continue to have leakage at the front, don't forget to check the dipstick tube. Mine had a hairline crack in the back that kept leaking, but was impossible to see. Finally found it only when the whole thing broke off. Good luck.
