Forgive me if this has already been answered, but as Bill said, the 360 used a larger radius pan than the 273/318/340.
The Schumacher website (
www.engine-swaps.com) has links to instructions for each swap as well as reference dimensions of common pans. There is a link to "Instructions" on their home page, and from the instructions page you can access the instructions for this swap. There is then a link to a page that has dimensions for common oil pans.
Per the instructions the swap calls for any center sump low profile pan from a 360 - have a look at the oil pans page and you should be able to find one you like.
In lieu of that, give Mike Schumacher a call at 206-364-7151, he'll know which pan fits.
Full Disclosure Statement - Yes, Mike is a good friend and business associate. But he makes good stuff and knows what fits what.
SC