Looks like a 'no-go' on using the HAP80 at 45W
The PACE Thermojet uses a 75W heater and operates at a nominal 480C
The cooling effect of the air flow passing through the nozzle assembly requires a reasonably powerful heating element. I suspect a HAP80 running at 45W will not have the required heating power for a decent hot air pencil, especially if ROHS lead free solder is involved. That said, I have heard of the Weller desoldering irons being used as hot air pencils. How well they perform, I do not know.
Fraser