Yeah lose that rubber cap, I had one of those on my 340 and it lasted 1 day. it looks real nice and clean but they suck. tap pipe threads into the nipple and put in a pipe plug. if you want heat just unscrew the plug and connect the hose. is it worth getting stuck or losing a Head for that?

71 challenger convertable, 64 sport fury 383 ci with factory air 99 sebring convertable 89 CTD pup