I've used that bridge a couple times now, and like it a lot. I'd have been using them a lot longer had I known about them. Highly recommended.
To get them to "drop in", you need to order the "Floyd with angled pocket" route. I think the option exists for those who'd like to "top mount" a Floyd. It spaces the mounting posts properly, opens the string anchor block cavity up a bit, and puts a couple degrees of angle in the neck pocket to account for the added height of the mechanical monstrosity that is a Floyd Rose vibrato bridge. The Schaller Vintage is fairly flat so it doesn't need the angled pocket, but I'm not sure you can specify that routing/drill pattern without it. If you can't, you can compensate one of two ways - either set your saddles up higher than usual, or keep them low and set your mounting posts up higher than usual. The second option is the way to go, as it maintains the built-in leverage the bridge has so the operation is easier due to mechanical advantage. Plus, it gives a wider range of operation than you'd get with it mounted down lower where it would hit the body if you sharp the strings too much.
Finally, the whole thing is smaller than a Floyd - the base plate has essentially the same footprint as a Fender AmStd two-point. I can't remember if it's exactly the same, but if any pickguard adjustment is needed, it's minimal or I'd probably remember it. I hate working on pickguards :laughing7: