My 1999 Yamaha C90 TLRX was overheating, so I decided to take a look at the impeller. I bought a water pump repair kit, upper and lower water pump housing. I've gotten down to the lower water pump housing, which has holes eaten in it. Last night, I pryed the plate of the housing up to remove the lower housing, and it broke in half. After removing the two halves, the top oil seal came out, and also an O-ring. I belive the bottom of the housing, which is the round part that fits to the top of the gearcase has broken off and stayed in the hole. Is there anything I can do to get it out? It seems to be stuck pretty good, and there's a good bit of corrosion too. If chipping it out is the answer, that's fine, but I really don't want to damage the gearcase. Should I stop now and take it to the shop, or can I safely continue if I'm careful?