Grant,although your clearances may be spot on,there's always the possibility of a burr on a bearing insert,a piece of crap somewhere, or something like that.
If you have any doubts at all,no matter how slight,pull the crank back out,yeah ,I know it's a pain in the [censored] at this stage of assembly, but.........See the crank spins freely without the seal,then do the seal.Once a piston and rod is installed and torqued down,try and move the rod big end back and forth with your fingers.Should easily move the 12 or so thousands of side play.This will tell you all is ok cause the drag of the seal and rings can mask interference problems.
The rubber crank seals are available at any parts store in a day or two.It's also my experience,a properly installed rope seal will not leak.These engines have suspect machining from the factory in the seal area,a rope seal is more tolerant than a rubber seal in this situation.
