quick question
 

I`ve already tried the search, What is the body mount bolt pitch/thread size on a 98 blazer? 1.25 or 1.75?

eh. not sure i know its a 15mm head. do ya have a ace hardware etc around you? Take one in and match it up.

Its 12m by 140mm, Getting em at fastenal and they have the 2 pitch sizes