There is not but a couple tenths of an ounce difference in the weight of a 46FX and a Saito 72. Either could be heavier/lighter than the other depending on the particular engine. Having thoughts of putting a spare 72 I have on hand in another one just as a comparison. The 46 with an 11x7 Master Airscrew prop will not give unlimited verticle, but its high enough that all you see is a speck.

I simply coat the inside of the fuse, particularly front and rear corners and the entire surface where the moneycoat was cut off the hor. stab with epoxy, slide it in, measure it to be square with the wing and fuse, pin it in place then remeasure to make sure I didn't mess up, then clean up the excess with paper towel'S and alcohol. Messy yes, but have never had one come unglued.
Verticle stab is done the same way.