Tips to remove Shock Resevoir (Bladder Kit)

"How hot do I need to cook this, for the loctite to let go?"

That depends how much force you use, the higher the temperature the lower the force required...

Since the upper body is already damaged, can you clamp on this area in the vice to minimize the twisting when you are cranking on it?

Other than that, make sure the reservoir is as clean and oil free as possible.  I would use 2 strap wrenches.  Get bigger ones.  Make sure the rubber inside the straps is as clean and tacky as possible.  Might even help to hit it with a shot of contact cleaner just prior to get it tacky.

You want to heat it enough that it it's almost too hot to touch for more than an instant,  If you do this and get 2 big strap wrenches to have good grip it should move.  You want to keep the straps as close down to the threads as possible to minimize twisting of the can itself.   But it's a delicate balance not to get them on the area you heated up.  I've had a few KTM cans where the can almost twisted and crumpled before the loctite let loose, especially when twisting them with a tool that is all the way at the end.

250C ??  Holy hell.  What kinda loctite are they using?  haha

Since the upper body is damaged, I would heat the shit out of that area.  The slight expansion of the bare aluminum should help break the thread locking compound and avoid having to heat up the reservoir.  Would also recommend letting it cool down before using strap wrench.  I melted one of mine trying to loosen while too hot.  

Side note: would be really curious to see the piston on that shock if you have the shaft disassembled also.

With using double straps ( good idea)  :

If you can, position one at the body eye end, Over the section going over the thread, and, the other at the valve end - With The End Cap Inserted.

I've seen reservoirs collapsed / distorted, by Not having internal support - some of them are very Thin.

If the reservoir is toast already, drill a hole straight through reservor and put a long screwdriver or metal rod in there. Twist.

Heat of course.

That's pretty low for it to soften!!

I know a few shops have had trouble with OEM shocks coming apart by unthreading on the 23+ gen WP shocks under heavy use. 

You'll see a variety of clamps and stoppers to help hold them together. 

The temperatures are in Celsius...

70% strength at 100°C (212°F)

0% strength at 230°C (446°F)

K-Tech Aust team's advice of throwing it in the oven at 250°C (482°F) would work.

I'm trying to imagine handling a 250C shock body, getting it in the vice, and throwing a few strap wrenches on it.  Doesn't sound fun.. LOL

That would be a challenge!

It should have lost it's strength after heating to 250°C, let it cool down first.

Heating above 150C (300F) will cause the aluminum to lose its temper. At 250C it will lose significant amount of strength.

The reservoir isn't structural, and it's anodized, but losing hardness of the substrate certainly isn't a good thing.