How do you change the pull cord on a Briggs and Stratton mower engine when it appears the housing is riveted?

I'm doing this now. i drilled through the rivets. started with an 1/8th drill bit and a little oil on top of the rivet. the problem is going to be finding replacement screws that will hold the starter cage once you have replaced the cord. some Briggs and stratton engineer needs to be taken to the wood shed.