Mopar M1 Manifold Injector Bosses, Not Drilled Out

The Ross tool is just a modified drill bit. It's cool for drilling existing bungs in one step but will not work for 75slant6 to modify his Crosswind. He just needs to order some bungs and drill the holes needed for the bungs with regular drill bits.
Incidentally, the OP could have drilled his existing cast-in bungs with two sizes of drill bits, and a quick chamfer on top. Some manifolds don't even use a stepped hole, just one size for the O-ring.