bb and guide installation

[Incorrigible]

Can someone walk me through the steps to install a 118 or 113 by 73 BB on a 2003 BB7, using an ISCG World Cup System 1 MRP system?
I give up. And I am about to give up riding the rate I am going. I am so frustrated.
I have been told many times that a compact race face north shore crank will fit with a 113 BB and an MRP system 1. No, it does not fit. It must be me, but it will not fit the tire, and the crank will hit the boomerang.
Don't tell me to take it to a shop. They have been useless so far.

[Incorrigible]

Problem solved. A little grinding here and there, and using the bb spacer on the 118 bb did the trick to keep the boomerang away from the tire, and the crank away from the boomerang. If anybody runs into the same problems, pm me. And thanks to Geoff Pendrell from Cove, and especially Robbie D from "Robbie and Dave's Machine Shop" in Cumberland Ontario for their invaluable help!
R