Well when I bought the truck I noticed the exhaust brake to be pretty touchy. Now I can't seem to get it to work right...If i shake the switch in the picture it will activate intermittently...? anyone know where to get one of these? I also swapped holes for my linkage worked pretty good!

 

That appears to be a standard switch that you should be able to get from a local electrical supply or electronics store.

 

Check the connectors. Mine got flaky. Turned out to be a wire loose in a crimped connector.