I'm trying to install a X01 crank onto my Santa Cruz Tallboy with a GXP Shimano bottom bracket. When I put the dive side on, a large amount of the spindle shows on the non drive side, meaning there is a gap of about 5mm after tightening everything up. I assume this means I need to put a spacer on one side or the other (or both?) but nothing came with the cranks and I can't seem to find anything about a spacer from searching. Everything I find, including the instructions that came with the cranks say that for a BB shell of 73mm no spacers are required, and if I put any more spacers, other than the 1 current spacer on the driver side, between the BB and the frame there isn't much thread left to secure the BB. What am I missing here?