he's gonna apply the copper cap in "the hose" (sorry don't remember which) to fix his moosing problem.
as for running injector through your manifolds, it's probably better than nothing. here's the thing, if it's never been done before, it wont really help much. there are people who've said a wire brush wasn't enough to clear away the carbon, and had to use items such as screwdrivers to scrap it away, so rinsing over them with cleaners wont penetrate enough to clear it all away. IMHO, I'd not waste the money, and just wait til you have time to actually clean them out. I've got 2 cans of Valvoline Synpower waiting to tear into them once I get ahold of some gaskets and a spare saturday.
