You can find "how to" articles everywhere on LS/VTEC's.
The GSR head would give you a higher compression ratio due to the smaller combustion chamber. I'd go with the GSR head, you could probably find one cheaper than a B16 or B17 head, and deffinetly cheaper than a Type-R. You can have the GSR head ported to make just as much power.
You do know the B16, and B17 heads are the same casting as the Type-R right? Just the Type-R has a mild port and polish job from the factory. Because of that, everyone and his brother wants a B16, B17 head to make a Poor man's ITR motor.

If you left your LS motor stock and slapped on a B16, B17, or B18C5 head your comp ratio would go from 9.2:1 to 9.5:1. If you used a B18C1 head you'd get a 9.7:1 ratio. Keep this in mind if you ever do a build up and get higher compression pistons.

Hope this helped a little.
-Wes