Hi my 1995 Mazda protege is overheating we changed the thermostat and hose. We bought a new radiator and when I am driving it, the temp gauge flutuates and goes to the H. Both fans work; Motor mount will be replacedue to excessive rattling while at idle. Car still starts andruns not sure about loss of compression. Greaton gas. Also my check engine light is on and my speedometer gauge does not work. Desperate for help

 

Sounds like you should have covered several things that would cause the overheating but it still is? Is the engine actually overheating or is perhaps the gauge sending unit just acting up?
CEL codes can be difficult to retrieve on a 95 but would try the Autozone route first and see if their OBDII scanner is able to retrieve codes. Code should start with a P and then followed by four numerical digits such as P0455.
Speedometer is probably due to the connection point between the lower and upper cables has broken as usual. The OE cable ends were plastic and tended to break. Replacement cables have a metal connetion point which is much more durable. The connection point area to check would be below and to the inside of the brake master cylinder.