Rant: my coilover install turned into a 2 day mess because of one seized bolt

Went to put new coilovers on my 2013 Civic in my buddy's garage in Sacramento last Saturday and it was supposed to be a 4 hour job. Got three corners done fine, then the rear lower bolt on the driver side was so seized that my impact gun just rounded the head off. We tried PB Blaster, a torch, and even a breaker bar with a cheater pipe, and nothing worked so I had to cut it out with an angle grinder. Ordered a replacement bolt for $9 and it showed up Tuesday, so the car sat on jack stands for 3 days and my buddy's wife was not happy about it. Anyone got a trick for rusted bolts that doesn't involve destroying the hardware?