Do not know about the sides, but this I can tell you.
The screws in the back are to hold the cooling coil tight to the back of the freezer compartment.
While those screws will come out, they will not release the back plastic panel. The sides, I'm not sure about. They "might" be snap in like you stated. I have not had the sides out.
This is out of a 2007 T286SR and is also a RM2652, just newer
The freezer and the screws in the back
The back of the fridge with the cooling coil off showing the freezer cooling plate those screws go through to hold the coil in place. There is nothing back there you can clean or take off to clean short of pulling the entire cooling coil. I doubt the smelly stuff made it around the screws.
Did you resolve the stink issue? Sorry late getting back to you, been out camping.
Hope this helps
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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