I’ve had one of mine soaking for months and applying lots of heat every weekend… not moved a bloody inch. I have been toying with the idea of producing in a special clamp cum separator that grips the barrels tight but between thew fins so that you don’t break them and then clamps across the crankcases so you can lever the two apart. Hadn’t even thought about the liners moving. Back to the drawing board for me I guess.
Good luck Brian.