I take it that you are planing to lower the stab on the fuse and going to build it with no anhedral. This was done on a later version of the Tiporare called the Tipo Plus (longer fuse). I have a fuse for one but no wing or stab cores. I know the this version had a choice of the anhedral stab or the flat stab (also had the choice of the original wing or new design). They used different stab cores for what ever stab you choosed. I do not know exactly what the difference was on the core from one stab to the other.... but from pictures I have seen of the Tipo + that has the flat stab. It looks to be not as thick as the anhedral stab. It also looks wider from LE to the TE of the stab (More area).

MK