Chevrolet Repair: 1995 lt1 corvette, coolant system, head gasket

Question
is there any other diagnostic for white smoke coming out of the drivers side exhaust(except head gasket?)..its a performance car ,not a daily driver.the thermostat, i believe stuck the other night, and it sent the gauge to the moon..then went back to normal.now i have white steam coming out of the exaust.the coolant system is very rusty.im flushing it this weekend,new thermostat..no engine code stored,no power loss no  water leak,no water in oil??????...i guess im hoping it not the head gasket.....wishfully thinking?...sensor?allnew o2's up stream and down less than 100 miles on them.can the reverse flow on the cooling system some how introduce coolant to the block if it is the thermastat?........$2300.00 estimate over the phone from the dealer for the head gasket!!!!!! lots of dollars in the performance up grades of this car...to many to list!!!thanks rob  

Answer
Hi Rob.... put a pressure tester on the cooling system. see if it builds pressure fast...also you can get a cooling system dye to put in. then use black light on exhaust pipe and see if dye showes up...will also show up on the plugs...if it is burning coolant. you can also put your hand over pipe and them smell it and see if you can smell antifreeze.... hope this helps....