A while ago someone on here recommended using a G Coupler on the grease gun. I bought one and used it the last time I greased the king pins. It certainly made the job much easier and I can also recommend it. I had purchased a remote greasing kit, but wasn't really convinced that it was the right thing to do so I didn't fit it, especially as I think it is necessary to get underneath and wipe off the excess grease, so what's the point?
https://www.amazon.co.uk/G-COUPLER-Coupl...words=g+coupler