Trying to ensure my rubber mounted dog bone bolts (screws?) are tight....and since I don't have that size, when I go buy it, I want to make sure it is the right size, so can anyone tell me the right size for the star bolts? It is an 09 1200C Harley. Also, underneath it appears the item that the bolts (screws) tighten into are round....what stops them from turning when you begin tightening up? Thanks in advance for your help.