In what way did the cranks not fit? All square taper spindles have the same angle of taper, but vary in high and low dimensions as well as the length of taper. I believe the Sunlite Cranks are JIS and there is a good chance that your current BB is as well, being manufactured by Tange, so it should fit. When you install it, does the crank go too far on the spindle or does it not go on enough? Also, that is a double crank and your current spindle is probably for a triple. The way I decide on spindle length is to install the crank on whatever BB I have handy, take measurements for the chain line and then use those measurements tell me if I need shorter and longer (and how much).