I was going to keep stock size in the back... that would keep the speedo the same, right?
the reason I was thinking of running the smaller tires up front is because they are already on the wheels. I can't afford to have them mounted and balanced. So I have to do it myself (no tire machine, tire irons, but I do have a bead breaker and a balancer) doing another two tires may not seem like a big deal (actually it would mean breaking down 4 more tires, and re-mounting two of them) but I had back surgery not too long ago, so it actually makes a big difference. Otherwise I'd just do all 4