2K paint question

[Grrrrrrr!]

I've got some 2k clearcoat that came with hardener, but it turns out that the hardener is f'n slow, when i really want a fast hardener. The problem: I can't easily get my hands on the right hardener.. can I use a different brand hardener without any major problems in the short term? Don't care if it goes yellow over time, just need something to make the clear hard enough to mask in less than an hour.

The panel is just a test panel, so will get sanded back again in a week or so anyway, I just need a fast hardener to get the next layer or three of clearcoat to cure while i piss around with flake & pearl to see what effects I can get.

[Quint]

Rent a kero burner heater thing (looks like a fricken jet!) 10mins with that baking the car and it'll be dry.