ORIGINAL: freeonthree
Moving the engine forward the thickness of plywood, will change the CG, but not enough to where you'll notice it in the air.
I have a similar need to extend the prop out by about 1/16 maybe 3/32 to clear the cowl. In addition to that the rocker arm covers all touch the cowl (Saito 170). I really don't want to cut the cowl if I can get away with it. I have not had a setup like this so I am not sure if having the valve covers up against the cowl will cause a heat issue.
Thanks in advance.