Nifty new project Greg! Hard to tell yet what make it will be.
But I'm sure it will keep you busy for the winter.
If I may make one suggestion before you get much further? Incorporate as much steel in the construction of the loader model as you can, the heavier - the better, especially in the rear.
Keep the loader arms & bucket in aluminum to conserve your hyd power to where it counts, but steel as much as possible everywhere else.