You can get a set of plans from Frank for any sort of smoker. Last year he had a nice smaller cabinet pellet driven rig but it could have had a GF feature.
Current Smokers: Backyard RF Offset and Hybrid RF Offset trailer rig with Cowboy cooker and fish fryer, always room for more........
No need to try to mentally scale it down...There are tons of plans not yet published...so contact Frank and he will be able to get you on the right path....
If you can't fix it by sheer force or cursing......then it can't be fixed.....