The Laura engine doesn't have a head gasket (at least not the ones I've had apart). I shaved .080 off the head to increase the compression on my Batavus. That translated into quicker throttle responce and overall snap to the engine.
I made an arbor that threads into the spark plug hole and was long enough to chuck in the lathe. I usually like to keep about .100 gap between the top of the piston and the end of the spark plug. With the head off bring your piston up to top dead center. Take a straight edge and verify that the piston dome just comes to the top of the jug. If it goes beyond the top of the jug measure that distance and make a note of it. Next, with the spark plug threaded tight into the head take a depth mike and measure the distance from the gasket surface (if it had a gasket) and the end of the spark plug. Make a note of this measurement because this is the distance you are going to modify. Take that distance minus the .100 gap, minus the piston height and you have the distance that you can shave off the head. I've had some heads that only needed .060 to bring them into my .100 gap limit. With the added compression you generate more heat so don't go to extremes and shave to much off the head. I'd start off by shaving .040 and see how it runs. The nice thing about this modification is that it is reverable in that you can add a shim the thickness of what you removed from the head if you want to go back to original. Mark the head with the amount you took off so that you remember that the head has been modified and by how much. I use a felt tip marker until achieve my final shaving and then I stamp it into the underside of the head. Check your spark plug after you've run the engine for awhile because sometimes you have to drop down to a cooler plug.
Good luck. If it ain't broke, you're not trying hard enough.
Brian
Lamborn's Miniature Engines
http://www.geocities.com/miniengine