no the ign sw is not fused, get an inline fuse to put in the hot wire or if you have a fuse panel with an unused slot, get power from there [best alternative] ... size usually 9-10amp, might indicate current draw on the motor, should say in the sales listing ... the multi-speed switches do get hot, but are mounted to the dash originally, there are no flammable materials under there except wiring, which of course you will keep clear of
I'd say if Classic Parts can't give you that advice, they shouldn't be selling the product - or you shouldn't be buying from them!
Bill