Is this a good idea?

Working on the motor outside the car is always a good idea, its MUCH easier, as far as the swap goes if you have everything to do it with, it shouldnt be too hard, but without the right tools its always harder.

You also get a spare engine in the bargain.

I would say that swapping engines is a bit more involved than a HCI swap, and you need a cherry picker, or some other device to lower the engine, but it isn't any more difficult, it just takes longer and some times you need two sets of eyes to guide the engine in.

p.s. look on the clearance page at Summit, I bought a Trick flow forged crank for $511 shipped. An american made crank for less than Eagle price. This will make an ideal foundation for a stroker.