I agree, very good tune up guide.
Tried it on an almost 'new' HW 95, what a difference (power up to 11+lbs & smoother). I also discovered that weihrauch (like most companies) make their guns down to a price. If you have the ability take them apart and clean them up, even if new!!
As for the degreaser, your local Motor Factors should stock aerosol cans of 'Brake Disc Degreaser' or suchlike. very strong solvent (clears most everything) & dries quickly, certainly worth a try.
Howard