I need help separating exhaust can from headers: V&H for FJ600

It all started with the fact that I had to remove the entire exhaust from my bike just to drain the oil. That was done sucessfully and without incident.
As you can see, the Vance & Hines system is functional, but rusty. When I put this pipe on my bike back in 1992 or so, all that needed to be done was to install the header, and then insert the can onto the header as a friction fit.
many moons have passed, and what you see are tow pipes that are pretty much stick together.
I have a friend who is more than willing to media blast the system, but it would require that I separate the two pieces.
I'd like to avoid cutting since a) i have no way of welding them back together and b) there has to be a better way.
I've started to wedge a series of small flat-head screwdrivers between the pipe fittings. before that I used tons of spray lubricants, a cheap belt wrench that I broke, a propane torch, and parts of my house that could brace the headers while I attempted to wrestle the can free.
I'll have another set of hands for this task in a day or two, but I'd love to have this problem solved before that.
Any ideas?

Get a gallon of Rust-Away and soak the joint in it...

I soaked the joint in what I had (a CLR solution) and it didn't help...at the time.
I did however, open up the joint a little more....which will necessitate a bit of cosmetic hammering later, and applied a liberal amout of heat. After that, a donor metal rod and my trusty rubber mallet, along with a beam in my garage to hold the header steady, and the parts finally separated.
Case closed!
See ya on the project threads below.