I am hiding my wires and connections underneath my seat, with fabricated cover plates and the cover for what used to be the tool kit.

My problem is the bolts holding the rear coverplate face the rear fender and found out that if I bottom out ( was either pot hole, swerve into my bud riding behind me closer than I liked or on coming traffic ) the bolt head taps the fender.

No luck at lowes ace or homedepot on a M8 bolt with a flat sitting low profile head.

Not too sure on what even to search for on the web.  I want the bolt head to be flat right to the threads like a "  T  " not the bevel on most countersunk bolts that  "  Y  " into the threads.

Dont know if that makes any sense at all but erm help..... the threads can be any length can cut to fit if longer than 1/2 in

cant use a carriage bolt. the head has to sit flush with the cover plate.

although
https://www.fastenal.com/web/products/details/0140682;jsessionid=QGfYVm3PxTYp...

closest I have seen but need M8 bolt size and threads all the way to the head.

sooo.. if I were to buy american "connector bolt" threw fastenal what size should I buy if I were to use tap/die set to thread M8 to that smooth spot on those bolts in the link above

perfect thanks serrow