[ImperialCrown]

After the next hot shutdown, look into the throttle body for fuel drips or fuel fogging. Hot restart issues are commonly caused by a rich hot restart condition.
If you hold your foot on the gas pedal ~few centimeters and it then fires up easier, that may be because of the extra available air diluting the rich mixture.
Some injectors/o-rings had a leakdown problem.

 

[Bob Lincoln]

You said 'either AIS or TPS' codes. Which is it? Or both? That's likely the source of the trouble. Could be a bad sensor ground. Check the ground at the driver's rear corner of the block - the lug under the bolt. The wire is too short on these cars, and can fray and cause intermittent operation. I've had to repair them in the last two cars.

You may have to unplug the ECM and clean the contacts on both it and the harness plug to it.

Don't run a 180F thermostat. The car is made for 195F, and 180 will keep it in open loop operation longer, which means worse gas mileage and emissions and power.

Did you change the dist cap recently, too?

 

[B10alia]

If the AIS and TPS check out, you could potentially be looking at a Hall effect sensor (distributor pickup). Usually they kill the car as well, though, when they start to flake out. Those and tired ignition coils tend to get upset when warm. But since you have the codes, I would go after those first, the Hall and coil are just suggestions in case you find that it's not the AIS/TPS.
The AIS is a bit difficult to test because it's a stepper motor, meaning you can't just throw 12V on it and see if it moves. The TPS, on the other hand, is a very simple variable resistor. There's a wire inside that contacts a wiper that's controlled by the throttle shaft. The computer reads the position of the throttle by measuring the resistance across the TPS. Of course, like any electro-mechanical sensor, the TPS can develop bad spots. If you have access to an analog multimeter, put it across the pins and turn the shaft (for lack of a better word; the bit that goes on the end of the throttle shaft). You should see a smooth change in resistance. Skipping or jumping indicates a bad spot. If you only have a digital multimeter, you can still do this test, but you'll have to turn the TPS very slowly so that the meter can "keep up".