I"m not qualified to answer the 5 wt in the forks question, but as far as the grease fittings go, they are often neglected. Clean them both with kerosene or other solvent, take a piece of wire or tiny drill bit with a flat end and try to push the ball down into the fitting just a little to break it loose. Then grease until some comes out each bushing. If your nozzle is too loose it will just come out around the zerk fitting, but some fiddling with the angle may allow it to work. Worst case, if they are frozen, replace them....not very expensive.