The engine is then all mounted up. The cowling needs to have the access holes cut, and clearance holes to get the cowling on when the muffler is on the engine. To do this you can use just normal printer paper. Tape the paper to the side of fuse as shown in the photos. Now the holes are made on the paper to fit the specific locations. Since the paper is attached to the fuse with Masking tape remove the muffler and attach the cowl. Transfer of the hole and access locations and sizes are made to the cowling. Cut the cowling as needed. The re-install the muffler and make sure you can get the cowl on and off with the muffler on. You will need to have a slightly oversized hole to the rear to get the cowl to clear the muffler and then stretch over the end of the crankshaft. The general holes and access for the needle valve, low speed air bleed and glow plug hole are then matched up.

Since the cowling has no venting for air exit in it you need to cut some. I choose to put a larger square hole in the bottom. This combined with the extra clearance for the muffler will give a good amount of exit air for engine cooling.