Generally in that situation we run the heat up till the metal is warm..then shut the heater off ..vent and shoot..then heat goes back on until cure is acheived..PITA..but what we need to do in the winter..
We use the infrared type heaters mounted on a roll away stand to heat the metal which is the inportant part to help us....also we have the thermometers that are the no-touch type to tell us the metal temp..That is the basic what we do in the winter in collision repair..
Probably one can get by by pointing an infrared heater at the metal until it is warm enough then shut it off while shooting and then turn it back on for the cure..One needs 60-65 + to acheive a good cure of the paint..this is not all that hard to acheive..
Sorry for the long answer..
I have tried most all of it and now do what is known to work..