First...congrats on your new purchase. Make sure you check out clarks-garage.com for info on your car. Now let's look at the problems...
If it's an 85/2, probably the speedo sensor on the transmission. Mine had a wire that was pushed out of the connector when I bought it. Fixed the wire.
Overheating engine and blows water out...this one isn't going to be as easy a fix. Blown head gasket. May also be the cause of the third problem.
make sure you know the condition of the timing and balance shaft belts before running it...make sure you replace them when you fix the head gasket along with new rollers, new water pump, and reseal the front of the engine. Should be a fun project. Hey, maybe I should come help you!
Amazing how having HI on your location line will get you volunteers, isn't it?