When I had to confirm the model data on my Thetford a couple years ago I had to place mirror behind the toilet to view the model number sticker, etc..
If you do have to remove the complete toilet to make a repair, make sure you have the complete seal kit for the model in question.
I had to replace my bowl seal (wouldn't hold water) last week in the middle of the National Forest..., glad I had a spare seal kit on hand (bowl seal & base flange seal). Truck tailgate made for a perfect workbench
2016 GM 2500HD 6.0L/4.10
2018 Jay Flight 24RBS
2002 GM 2500HD 6.0L/4:10 (retired)
2005 Jayco Eagle 278FBS (retired)
1999 Jayco Eagle 246FB (retired)
Reese HP Dual Cam (Strait-Line)