Same here, old guy. When lowering or lifting just the lower unit, I have used wood blocking under skag, then another old helper crank the trailer jack. Of course you still have too wrestle the shaft up/under the upper 🤷
I put it in freezer overnight.
Transferred it to small iced cooler.
(Left room for beer)
Heated gimbal area with hair dryer.
Ready nylon punch n hammer.
Removed from ice.
Tapped it in place, didn't go real easy.
Worked for me.
If you bought a complete kit, the pump should have been in it. You may have to adjust the cam plunger for stroke. Setting should be on instructions in box. Of course I haven't bought a kit for years so they might not sell a complete one now.
I have ground a screwdriver to fit. But didn't want to destroy more of them. I now use a 3/16" steel drift punch and hit the corner using ball-peen hammer to loosen. Replace as needed.
