Was doing a chemical flush of the cooling system per my last post and trying to get 3-6 hours of engine time before cleaning it out and 45 minutes into idling in my driveway smoke starts coming up from between the two seats and lifting the flap in the carpet where the seat belt comes out of the temperature reads 360 on the metal there and under the car the main exhaust pipe read 400 degrees and the thermal reactor was reading 580 degrees when I shut the car off.

this seems abnormal, is this a clogged exhaust or is this a heat shield failure or does anyone have any suggestions?

 

Unless you have a rust hole, that area is completely sealed. It could be a clogged exhaust, but given you said you had what could be higher water temps, you might have a bad rotor seal and what you're seeing steam.

I'd remove the heat shield from the exhaust to inspect. You might also remove the seats and pull that carpet back.

Also, those seats don't look like 1980 seats.

 

They’re 1983 seats as the ones I had in the car were completely thrashed. I’ll take a look at the exhaust system and appreciate the tips

 

Do you have an exhaust leak somewhere? Whether a leak or steam from somewhere, I've saw vapors / fumes collect in the transmission tunnel and get funneled to the rear, traveling down the tunnel. If you have a small rust hole, missing bolt or tear in your rubber isolation boots around the shifter, the fumes could migrate into the cabin.

 

The thermal reactor will reach very high temperatures, this is normal. The exhaust leaving the engine will be near 1500 degrees, so expect higher temps at the thermal reactor. The heat exchanger may have a hole or a rotten or warped flange, which is causing the exhaust to be directed onto the floorboard. The smoke could have been the carpet backing melting or perhaps the sound deadening melting as well. A clogged heat exchanger can also cause a lot of heat buildup on the floor. I would look onto the cause of the heat and fix it right away.