Thanks for the suggestions. I should buy a set of left-handed drill bits someday.
I got them out
![up up](/ubbthreads/images/graemlins/custom/thumbs_up.gif)
, but not without a struggle. Tamper-proof, my ass
![punkrocka punkrocka](/ubbthreads/images/graemlins/custom/punkrocka.gif)
First I tried to get a 1/16" welding rod to stick (usually the opposite of what I'm trying to do!)
![haha haha](/ubbthreads/images/graemlins/custom/haha.gif)
, but ended up gouging a small pit in the plug instead.
It had gotten hot enough that the temper was gone and I could drill into it with a #36 (picked that size in case I had to tap for a screw thread) deep enough for an easy-out.
For once, an easy-out actually worked.
![shocked shocked](/ubbthreads/images/graemlins/custom/shocked.gif)
Turns out they aren't welch plugs but a piece of solid steel rod about 1/4" deep.
![eek eek](/ubbthreads/images/graemlins/custom/eek.gif)
Now I'm going to cut a small screwdriver slot in the heads of the needles with a Dremel cutoff wheel so I don't have to use an Allen wrench and hope it doesn't strip out. Then it all goes back together.
Here's the "before" picture of one of them for TJP
![scope scope](/ubbthreads/images/graemlins/custom/scope.gif)
(The secondaries have the bosses also, but they're not drilled. Just a "dribble hole" in the venturi).