*Note* I am not a Jeep expert and I did NOT sleep in a Motel 6 last night...
That said, I really think that you need a bit more clearance for safety. It would seem to me that with a fairly large displacement straight six, there could be more of a whipping action with the crank, a little bit of flex, and the inevitable expansion of heated parts. Plus, let's be honest, Jeep manufacturing tolerances are not the same as Porsche's - LOL!
The .125 in the afore mentioned robust casting certainly seems safer to me. I'd be much happier to accept a failed oil pump than a crank-pump collision...
angela