i had a guy run my 88(same engine) hot like that...the very first thing to do is compression test before spending any money on it...if the compression is good then wiring will probably be the only thing to repair...maybe head gaskets...retorgue the heads any time a motor gets hot...if i remember the book calls for 20 pounds on this with a recheck after running....do 22 to start with and the recheck will be right on.. dont forget water impeller..it will need replacing also... depending on how hot it got some of the wiring may be welded to the heads or block... if the compression on any cylinder is out more than 10% then pull the heads and eyeball the walls...why didnt the alarm go off...are the sensors disconnected?