The first time I've been afraid to rebuild a carburetor

Pump leaks are notorious on Holley carbs. Get real fine sandpaper, lay it on a flat table, take the pump cover and LIGHTLY sand it in one direction until all four corners clean up. MAKING SURE you keep the pump arm from touching the sandpaper. They won't leak again (fresh gasket of course). Definitely rebuild. Gas leaking on a hot engine is NEVER good. You don't want to watch your baby burn down.