I am rehabbing an old GT Rave (late 80's beauty). I already replaced the downtube shifters with SORA 3x7's. Now I am replacing the Exage wheelset with a set of Shimano WH R501 wheels. The problem is that the spindle for the cassette on the WH R501's is longer than the one on the wheelset I am replacing. I am assuming that I can just put a few spacers on the new wheels to compensate but wanted to make sure that I was not missing something that made it more complicated that I was assuming. TIA.