Lately my 86 RX7 has been consuming coolant. There is wet grime with a greenish tinge (my antifreeze is also green) visible on the front of the engine just below and to the passenger side of where the fan is attached. So I'm thinking water pump is going...

Anybody dealt with similar symptoms recently? Could my diagnosis be wrong? Any chance that it's just an o-ring or similar? (Didn't really think so...) Tough job to do yourself? Where'd ya get the replacement water pump? If you had a shop do it, how much did they charge?

Thanks!