Just sharing this as a tip. If you don’t like it, don’t do it.  I shared this in some the airhead Facebook groups, and, as you know, you can draw some negative comments. 

I have done this 4 times now with total success. In each situation I needed to remove the cylinder heads, but had no reason to remove the cylinders from the crankcase. I used hardwood (oak) slats, ripped just over 1/4” thick, tucked between the cooling fins at the top of the cylinder and tensioned back to the frame with wire ties. This held the cylinders tight to the crankcase while the heads were removed. I then used 1/2” cpvc pipe spacers / washer / nuts to hold while the head work was being done.  Picture attached.