hey guys I just picked up a used/rebuilt pump. It is a 12jc with an "AA" impeller. Any tips on installing this thing before I get started? It is going into my 21' Charger. The boat that had the engine water or lack there of problem. New engine coming soon. I have had nothing but problems so far in my first jet venture, so any help ahead of time would be great. Tired of screwing up and asking questions later.....