Thanks for the idea but this is the brakes we are talking about here! I think I will stick with the machine shop.
I do not mind getting stuck in with the grinder or recip saw where appropriate but the brakes! are you crazy? This will cost me less than I paid for the caliper and I can ride knowing everything is straight and true. Full contact between the disc and mount, as the manufacturer intended.
Sorry mate but I just can not do it!