Adding a hydraulic top link is pretty simple. You just need to get one with the correct pin size on the ends to fit your tractor (I believe yours would be a Category 1) and get the correct min/max length (your current top link should be instructive for those dimensions). You plug it in to a remote circuit and run it like any other implement cylinder.
There are two potentially more difficult things: 1) If you don’t have a hydraulic remote circuit to plug it into you need to install at least one. Some people seem to find that a reasonably easy job, others not so much. 2) Paying for it. Particularly if you have to add the hydraulic remotes, it can get painfully expensive. If you already have an available remote circuit (I don’t have a backhoe but seems like you’d have to have one left over after removing the BH) you should be able to pick up a top link for under $500. That could be from someone like FitRite who will probably assist with sizing and walk you through any questions you may have or from a commodity type supplier such as TSC or AgriSupply.
One additional thing you’ll have to decide is whether you want a top link with check valves or without. Some have check valves in the cylinder such that the cylinder is locked in position until you apply hydraulic pressure in one or the other direction. That can be helpful to override any leaky valve type issues the tractor may have which would allow creeping of the top link. But you can’t float a check valved top link. Ability to float requires connecting the top link to a hydraulic circuit with a float detent valve.
Personally, mine does not have the check valves and works just swell. I wanted the ability to float it but some may have no use for that.
Attached a couple of photos. I think you can see it’s really just a hydraulic cylinder hooked to a remote. The trick (if there is one) is sizing it right and enduring the pain of writing the check for it.
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