This would be tough to give a precise/complete set of changes for people here and for the RT people also. The reason is that the factory makes changes without RT sales folks knowing about them until they see completed RT29 CB models.
Minor changes can occur within a model year and more significant changes made between model years.
Some R29s will have more or less teak/holly floorings, more or less flip down step bars, some with and some without cockpit sinks, some changes in cabin's teak paneling, some with devices in different locations such as water heater, batteries, pumps, depth transducer, brands of bilge pumps, location of switches, different command bridge electronics, and so on.
I suspect the biggest change would be the Volvo Penta D4 engine. I think it started off as a 260 HP and today it's 300 HP.
To get more precise details of the changes you will need to talk with Ranger Tugs.