Re: Followed Stewmac diagram... no sound...
Apparently you didn't follow everything to the letter. All it takes is missing one connection, or making a wrong connection, and we've all done that at some point. Review it again to verify it to the diagram, it's easy to miss something, especially if you're new at this. Look at the hot wires for the bridge and all their connections, then the neck. Make sure every electrical part is grounded and linked together in one big loop. Verify every soldering is firm by plugging in and wiggling the wires. Also make sure there's no wire strands that could touch anything else; the soldering points should all be clean.
Did you try it with the cover plate on? Sometimes everything works, but when you put the plate on, a wire or connection gets pushed and grounds out. If you have push-back wire, accidently grounding-out is a common problem, and I'll use a small piece of bubble wrap to keep it from touching anything else.