Drilling a cap screw head
 

Can I drill the head on a couple of cap head screws to wire a muffler tight. Any thing I need to do to the screw first? Thanks

Drilling a cap screw head
 

You don't have to do anything, really... but if you're talking about the
socket head screws with the ridges on the outside, I used to grind the
ridges flat with my dremel, just to make it easier on my drill bits.
(Just grind the ridges flush with the head, at the place where you want the hole)

The actual drilling should be done in a drill press if possible, and using carbide bits.
You can do it without either, but you may end up breaking bits.
At any rate, if the bolts are grade 8, you'll probably waste a bit or two anyway.

Drilling a cap screw head
 

You can buy them pre-drilled at most any racing speciality shop.