i have a 89 mz20 , had it four about 5 mnths now been off the road for nearly 3!
the head gasket ( no suprises!) began a slow leak , about 3mnths ago , began heating up then over a mnth got progressivly worse untill i couldnt go about ten min under 2500rpm, without pissing about 1ltr of water out the overflow!
the engines out and head off, the the only problem with the copper gasket appears to be a small leak in cylinder 5 joining the cylinder to the water jacket. im looking at rebuilding the engine and getting a manual half cut, but having some fun finding one. but its still the schmickest car ! and wouldnt give it up! ( unless it was for a working man) there easy to get power out of ( as long as u keep the gasket down), and they handle beautifully. like driving ur lounge around the streets , but with climate control!