I've done more than my fair share of these nasty things it seems.
The worst one took me the better part of 2 hours to get the bolt out of the rusty hole it lives in. The easiest was just light pressure from my finger!!!
I dismantle the entire rear swingarm and suspension components and grease the entire system from one end to the other. Why not? You are that far into it you may as well do the job right IMHO.
Once you have the wheel, brakes, chain, sprocket, linkages or dog bones out of the way you can go after the rear shock, shock pivot. You need to loosen one engine mount bolt that lives near the swingarm bolt and is a 14 mm nut and bolt. Don't forget to retorque it when you are finished. If you don't loosen this bolt, you will have a huge issue trying to get the shock pivot out of the frame as this bolt pinches the frame together and also pinches this pivot at the same time.
I use a solid brass punch to gently or violently beat, it's their choice as to how much pressure get delivered to the two bolts that need removing. Once out, I remove the seals, check them for damage, if the bearings are in good condition I leave them inplace. I clean the whole system within an inch of it's life. I install the old seals if still usable or new ones.Then apply generous helpings of marine grade grease to all bearings and all seals etc. I also fill the frame cavity with the same grease to try and stop the same corrosion from happening again. Then I take each bolt and run it through the bench wire wheel to get it back to the way it should be, clean and shinny. I then coat the bolts with same grease, reinstall the whole assembly but don't attach nuts yet, I clean the threads off on all bolts with accetone and apply some of the good blue loctite to each thread and retorque to spec. Then finish assembling the rest of the system and bingo bango....job's done.
Don't forget that rear lower engine bolt......clean and retorque with blue.
Hope this helps....a very simple explanation......there are a few smaller items left out as I'm sure you will figure them out as you go....just simple things.
The hardest thing to do is to not beat the daylights out of that stuck bolt with a steel punch so you don't ruin the threads up so much you need to replace it after you get it out because it's mushroomed. Use a good brass punch and a heavy hammer.....tapping it with a small hammer will get you nowhere!
I also don't bother with prelubes etc....I find that if you turn the bolt in the case or frame it will move after it gets a few good shock blows from a large hammer.
I will admit to ruining one of my bolts the first time I changed mine....I used an impact hammer and beat the daylights out of the threads in a matter of seconds! Just don't copy my mistake and take your time if you need to get the big hammer out. A few well placed blows are better than a thousand ill placed hits from an impact hammer.