Finished up fine using my drill jig which requires 1/16" drills. Cobalt worked out ok. Wanted to use 3/32 but would require drilling of jig pilot which is at least as hard as the bolt heads
. Main thing is to have patience. Light pressure and clean chips often. The crunching sound that happens in the middle appears to be because previous chips can not escape and get ground up. Not a great thing. Clearing chips once crunching sound starts then re-
oil and continue seem to work well. Just installed, torqued and safety wired.
Thanks