I bought an Addington thumb several years ago, because I had read rumors on the internet that the Deere thumbs were soft.
Welding was required to install, and the pictures of Deere thumbs I have seen are close enough to the Addington one, that I believe welding will be required for that also.
I called a mobile welder who advertised locally and he showed up in a beat-up old imported pickup truck crammed full of every imaginable welder, clamps, tools, a generator, etc.
We pulled his truck up to the tractor on a fairly flat dirt area and he looked over the situation. Said "no problem" and welded one plate for the attachment of the hydraulic cylinder on the dipperstick. The he helped me install the rest of the thumb, which was quite helpful because the parts are heavy enough that lifting them into place and aligning them is not a one man job.
Less than an hour later, he pulled out a can of Rustoleum primer and primed all the places he had ground down to bare metal and I was good to go. The cost was either $50 or $100, don't remember which.
Tips:
1. have your own can of Rustoleum primer in case your welder doesn't have one.
2. Have a can of JD yellow touchup spray paint on hand, and some masking supplies. You will need to get everything back to JD yellow sooner or later, might as well do it now.
3. I think I got lucky. Neither one of us knew that we were supposed to disconnect the on-board computer before welding, and we didn't. Fortunately it didn't get fried. YMMV. I would look up how to disconnect it before the welder starts and do that for him, just to be sure.
You will love a hydraulic thumb. I use mine all the time. Last job I did involved reaching down over a retaining wall amongst some trees, picking up a boulder and then using the creeper to move the rock forward and away from the top of the retaining wall without damaging any trees. Had to manipulate the boom, dipperstick and creeper a little at a time to pull the rock out of a very small hole, but it worked perfectly.
