Dear muskox37,

Hope you're well. You're correct: some jobs simply need the tools/insights of a full-time, well-experienced pro.

A good way to limit disassembly risks is repeatedly to saturate bolts and nuts with PB Blaster or a similar penetrating oil. Given time, these oils find their way along micro-channels in the corrosion, and can weaken the corrosion bond betweent the fastener and the surrounding metal (if a bolt) or between stud and nut.

When seeking to remove nuts from a stud, it is helpful to remove all corrosion from the exposed part of the stud. Doing this eases the entry of penetrating oil. Further, the more of the stud that is "clean" of corrosion, the easier it is to turn-off the nut. That reduces stress on the stud.

It also is helpful - after penetrating oils have had a chance to work (daily saturations for several days may be needed) - to micro-tighten the nut or bolt, before trying to loosen it. Rarely are nuts/bolts tightened to the point where a .001" (one thousandth of an inch) movement will shear the bolt's head or the end of the stud. Thus, a slight tightening movement starts the process of freeing the frozen fastener. Then, one can then make a similarly-small but opposite movement, i.e., one should move the wrench in the other direction. If there's no give, apply more penetrating oil and wait.

All these things done, there are fasteners that will have to be drilled-out. Yours may have been one of those.

Hope this helps.

Yours faithfully,

Spook