I am building my first model and am currently at the engine mounting step. The engine I have is a OS .46LA. In the instructions that came with the plane it called for 1/8" holes in the mount and installation with 6-32 1" bolts. The manual that came with the engine called for 3.5mm bolts.

In either case, the bolts don't fit through the mounting holes on the engine - they are too large.

Am I supposed to force thread the bolts through the mounting holes on the engine? Is expected that the user will tap these holes to the thread size of the mounting holes? What to do?