Sorry Steve - when I reference Bill, I was just referring to doing it yourself - but if I was doing it, I would likely take the PowerPack out, and replace some of the other seals as well. I recently had a leak on mine and had to replace the o-ring and the backup ring on the "landing gear down" fitting on the bottom of the unit - was just old and installed improperly and finally started to leak.
Bill's suggestion of going through the top is not a bad idea if you don't have too many avionics in the way - mine has good access since I installed G5s in the panel.
I like the chainsaw analogy - ha ha. I suppose even a handpump set-up could be used. I have used this handpump in the past for engine pre-oiling. May work for this? I think you can find higher pressure ones...
https://www.amazon.com/VEVOR-Hydrost...89684056&psc=1