I was going to leave it stock...

Sometimes even a proper break in isn't enough.
I wiped 2 Comp Cams in a row even with proper break in with the cam and lifters lubed properly.
There are some things that you can do to improve your chances of success. Check to see if the lifters spin free in the bores. They HAVE to spin or they are very likely to fail.
Make sure that you have fuel and spark before the first fire. Cranking and cranking to get gas to the carburetor wipes the lube from the cam and lifters within seconds.