It wouldn't be a waste if you stopped. no one said throw it away. You could build a trainer kit and still fly something you built. If you crash it then that is the wasteful thing.

But if you are determined to build and fly it then the cowl is a simple matter of using a balsa block to create the form and shape of the forward fuselage by sanding and carving and sanding followed by some sanding. hollow it out to allow for engine clearance etc. dont worry to much about how it will look, the cowl never survives the crash.