removing exhaust pipes when pulling an engine

Run the engine until fully warmed up, shut down, put on the welding gloves, remove muffler, wiggle/twist the head pipes loose while still hot; if not practical to run the engine, apply heat from a heat gun (this will take some time) but if this is unsuccessful, ship with pipes attached and pay the service center to remove them?

Thanks, Jim! 

Alas, no, we can't practically run it, nor will it fit in the crate with them on. 

A heat gun might be an idea.  Do I heat the cylinder head, I figure, or the pipe?

Thanks again :-)

I would heat the cylinder heads and cool the pipes.

Might be easier to build a custom shipping crate! Or, as it’s on the way in for overhaul anyway, remove the cylinder heads along with the pipes. Speak to the overhaul center before attempting , but this should not be too difficult.  Be sure to mark each one so the center will know what cylinder it belongs to.

James Ott wrote:

I would heat the cylinder heads and cool the pipes.

Hi again, all!  Thanks for the replies.

In the end, this is what worked.  After 4 or 5 hits with pen oil over a day, dry ice on the pipes to ~30F and a heat gun on the cylinders to ~90F let me tap them loose with a dead blow hammer.  They wouldn't get going with just tugging, but it took very little to get them started with Mr Orange.  Yay :-)