Hey man, cruiser is looking good, you must have patience, way better at body work than I am, hahah!!! I also ran into the same engine stand issue when I took my F out and put the 2F in, except I had a stand that I rotated and it fit, and it only had holes(not slots) like yours, but it didn't matter anyway, as soon as I started to let the engine hoist down it bent the stand up anyway......Bahahha so my dad just has to put up with an F sitting on his floor until I get a better/Stronger stand!
PS: I'll have to send you a message the next time I'm headed your way, or try to pawn off my crazy cruiser parts collection, hahahha