Extract exhaust bolt: weld nut or drill?

[Boogle]

Originally Posted by S50Sinner

Arc-welding shouldn't transfer that much heat to the head if you just weld one tack at a time. You can get a spot-weld with decent penetration and cause no damage, as long as you let it cool down between welds. Don't go all the way around in one go, and you'll be fine.

Higher amperage should work better, as the faster you melt them, the less heat will pass through to the head.

Thanks for the advice - makes sense. Will try to follow it!