Place a new Quick Fuel Slayer series 600 carburetor in my ‘73 F250. I noticed with startup and while in park, I accelerated the gas peddle and the rpm’s stayed high up to four thousand even after I let off the gas peddle. I’m not sure if it’s a sticky throttle rod issue or the carburetor linkage. Anyone know what it could be? Thanks for the help

 

assuming you have the throttle return spring connected?
disconnect the throttle linkage to help isolate the issue to the carb or your truck's linkage.
if the carb itself is sticking, loosen it an make sure the butterflies aren't hitting the gasket...

 

Make sure your throttle plates aren't hitting anything and are returning to full closed position. sometimes the wrong gasket will do it, or you may need a spacer to clear the manifold .