If you can swing it than yes, the later model would be better. If not, that 94 would do a good job as well. While youre shopping, Im not sure if the 5 series continued it, but in the 2s the Custom Harvestor Special is the model to look for, they had the bigger header lift cylinders, chromed augers, and the larger final drives all standard

As the mods go, the feederhouse floor kit is a must IMHO, it really makes a difference in beans. That you get from the Butler store in Hoople ND. It was owned and still run by the Hurtt family. Just call them and tell them what you have and they will hook you up. A couple of days and a welder, torch and grinder and youll be done.  

The spacer bars for the CDF we got from AGCO. The Sweep kit came from Sunnybrook via AGCO. Top feeder shaft, sprockets, and hub to eliminate torque limiter as well as the extended helicals are all OEM Gleaner parts.  Chopper is a Rodono and lowered chopper floor, both came from PFP. Feederhouse corner cover was homemade.

The fine cut chopper will help some, but alot of people dont realize that it does take some tinkering to make them spread residue evenly because theres 2 discharges instead of 1. By playing with the paddles on the spreader and the vanes above the shoe they can spread pretty even. We do a better job than some of our neighbors with much newer JD. Another thing is it depends on the amount of material, we combined some poor beans this year, 30bu/ac and werent happy with the residue spread, but when we got into good beans again it was fine, there just wasnt enough material. PFP also has some extended vanes if you feel the need.

As far as capacity, the only difference between a 6 and a 7 of any series was the HP, I "think" the grain tank was the same, just the extensions were different. There might be some capacity difference only from the extra HP, but after doing the mods HP is not the limiting factor.  Somewhere out in the world Gleaner made a booklet a few years ago that explained the differences between models, what improvements were made in certain years and what could be retrofitted on to older machines. Maybe ask a local dealer if you can get a copy or call AGCO and they should be able to send you one. Its called "Guide to pre-owned 2003-2015 Gleaner combines". I know that anything newer than 03 could be retrofitted with the 2 speed hydro, which would be awesome if you had hills, unfortunatly no one could tell us for sure if it would work on our late 02.  

As far as swiveling the auger in and out full, yes they are much better than the older models, but as always if you can empty it, its definatly better, but it wont break it by folding it full.    

If you have any questions, email works fine.