Ok, so I tried this today. I put a SSC P4 USX0H in my MagLED 2AA. It was pretty much similar to modding the 2, 3, or 4 cell drop-in for their C and D cell lights.
A couple of pointers.
1) Get the "pill" out by pushing on the black base portion of the Luxeon LED towards the bottom on the light (obviously you need to take out the batteries first).
2) You will have to either cut off the small unbent exposed leads that extend out the side of the SSC, or file on the black "pill" holder as to not interfere with them.
3) If you don't shim the SSC the max throw focus point is very close to the
point where the light it turns on. I did not shim mine however.
I will take a kitchen bounce test shot later tonight when it's dark to see how it compares to the shot I took previously when it was stock for overall output. I can say that before the 3AA MagLED was much brighter than the 2AA. Now the SSC 2AA is noticeably brighter than the stock 3AA.