Bullseye, how exactly did you drill yours out? What size of bit? Did you hollow them and beat them out, or try to just drill the whole thing away. Sounds like a pretty viable aternative. I have already seen the rot from the bottom of the tub where the bolts are. Roll bar bolts are demoralizing.
I'm sorry it took me this long to answer your questions...I have been out of town.
So the thing is, I didn't really take any pics of the process to drill bolts. But below is the pic of the heads that will pop off when you drill and the other is the pic of the seat belt anchor bolt that was soooooo much fun to get out.
To answer some of the questions from your other thread and here:
In my case the bolts were just frozen. Blow torch, WD 40, liquid wrench, impact driver, air impact wrench just didn't work. Most of the bolts were Torx and stripped almost instantly.
There really isn't any exact protocols I followed but what I did for each was:
1) Hit it with liquid wrench long before I started.
2) I used a smaller bit to start the hole. I would use a hole punch but with the Torx bolts, but there is already a hole there in the form of the stripped out "star" where you stuck in the Torx wench.
As I stated earlier, I basically killed each bit on each individual bolt. So I would buy a set of packaged bits usually from ACE that were on sale. Like 10 or 20 in the pack.
I would use a small bit a remove an inch or so of material, or however long the small bit lasted.
3) I would then use a bit roughly ALMOST the size of the bolt.
So I would efficiently destroy the smaller bits then use a couple of the medium size bits and destroy those then have a lot of large bits leftover.
I did buy some of the super pricey individual bits for like 10-15 bucks a piece, but found they did not last all that much longer than the cheap sets.
4) When I completely drilled thru the bolts, I would again spray some liquid wrench and hit the little fraker from underneath with a hammer and that would usually bend and collapse the bolt enough to pop it out.
Sometimes I would use a set of vise grip pliers and crush the bolt in the hole as well.
Either way worked or I combined the 2 methods.
I also remember using an old chisel and hammer then hitting the bolt with the corner of the chisel from the outside bending the bolt in on itself. Then hitting it with LW again then using the vise grips.
Each bolt took me at least a 1/2 hour and those damn grade 8 seat belt anchor bolts took even longer.
Yes you will need an electric drill. Preferably one with a 2nd handle for your free hand to put added pressure down. JMHO of course.