Why bother doing both a window and a wot switch? Put the window on and you can run both systems through the single unit, and the system will activate once it hits the desired rpm and of course shut off at the designated equivalent. As far as running up to a 125 dry, in my opinion that is pushing the boundaries for the stock fuel system, not so much the bottom end. The LS1 bottom end can handle 150-200, not saying I would do it on a regular basis, but I would first put in a fuel system or at least an upgraded pump to compensate for the cooler air which you are going to be pushing through the MAF.
Now as far as dual staging both kits and running through the same window switch you would need a progressive controller, otherwise both kits are going to kick in at the same time and shut off at the same time respectively. You would need to control the impulse rate of the seperate selanoids to have a true dual staged effect. Hope this clears a few things up.