XJ6 S3 - Separating rear exhausts

I (think I) need to separate the rear sections of the exhausts from the bendy sections before them so that I can remove the IRS unit. I've undone the bolt-together exhaust joints but it's the push-fitted join just forward of the rear silencers I'm unsure of how to separate. I don't want to cut the exhausts because they're stainless steel and obviously I'd like to re-use them. Of course the XJ6 manuals just give the advice "separate the exhaust sections"...

I suspect that I'll need to heat the join - with one of those disposible canister torches (with the fuel tanks drained first!)?

I'm pretty friendly with the local exhaust guy so if it's something a bit too skilled for my DIYing I can probably get him up, but that would be against my doing it all myself aim.

Any advice will be most appreciated.

Thanks,

Jonathan

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