Sorry, I have been taken out of service by a total knee replacement. Among many other things, I can not drive for 6 weeks!@#$%?*&. I did get a couple of solid leads to places in Kentucky and PA but have not connected with a used set of Ag rims that will fit my 1620. Thanks to those who responded and tried to help me. I also reviewed many suggestions that advocated for alternative solutions using a combination of new R-4's on the front and turf tires with chains on the rear. Several entries reported satisfactory to very good results. With winter bearing down on W NY, I felt I was out of time. Following one suggestion, I purused Craig's list Buffalo and located a set of chains in excellent condition for $200 that were close by. I picked up a new set of 6 ply R-4's for the front for less then $275. and a neighbor mounted the tires and cut down the chains, deflating the loaded turf tires a bit. He snugged the chains up and re-inflated the tires to specifications. The very next day came the test. Another neighbor managed to bury his 2120 (with turf tires - no chains) in a swamp a mile back in the bush. The little 3 cyl 1620 now with R-4's in the front and the turfs with chains snugged up on the rear, pulled that 2120 out with little effort after it had been back there for a month.
This "change over" with labor was less then $650. The wheels (AG) f0r the 1620 would have cost (new) 0ver $2500 alone, at the NH store new, no tires, no "loading". . no labor. So again, I thank tractorbynet and those who participate in the blogs / forums. Now that I am retired and have a new knee (ouch!) I hope to take advantage of this "tool" more often than I already do..........
There are a couple notes of caution as with most projects: The chains will "mar" concrete that is pristine. In addition, the chains on the rear turfs will cause the tractor to "rock" a but, to and fro on hard surfaces at speed.
Regards........CSL112263........Western NY