> > > I have read almost every post on this forum...
Ha! Ha! If you're anything like me you're probably more confused than you were. Ha! Ha! And reading various books will leave you the same way, but I still believe in reading them.
OK, I see where you're at, now, and realize you're not just being lazy, or just didn't think about searching the forum. You're stuck at the crossroads without any recognizable signs of what direction's what. Even though you've got a full tank of gas you don't feel like listenin' to your ol' lady constantly say, "I told you that you should've stopped & asked for directions!"
Drop the ol' lady off there in the middle of the desert, Frank will be by before long & he can give her a lift to the frog breeder's house.
Alright, alright, enough cuttin' up.
I don't think anyone would argue much that a varied diet is good for any animal. Since we're talking savannah monitors here, most discussions I've seen on it have to do with whether or not it's necessary.
The only controversial part of a monitor's diet I've seen is the use of parital prey and not whole prey items (pieces of meat, ground beef, strips of chicken, etc..., versus whole rodents, whole chicks, etc...).
There are some here that have raised monitors on varied diets including invertebrates, rodents, quail, chicks, etc... And there are some here that have raised monitors on crickets until they're big enough to eat rodent pinkies, and pretty much nothing but rodents from there on out. I'm in that last group, but I'm also still a newbie, with just over 1yr of keeping varanids.
Based upon what I've read & seen mention in discussions, either route will get you there, but one route may be harder for one person to take while another can breeze down the path. Can you afford to buy or have time/space to raise, roaches, millipedes, scorpions, chicks, rodents? All of them or just some of them? Only you can answer that one, and I hope I'm leading you in the right direction to make the decisions you need help with. 
On caging material, pay close attention to every post within the thread "Monitor Enclosure Advice or Picture" a few threads below this one.
This is where giving advice can come back to bite the one giving it. If I tell you that you should build a sav cage out of 2 x 4's, with cardboard lining, a couple of days later you'll be posting, looking for me, because half of the dirt will be on your living room carpet. Then I'd have to change my username, AGAIN. I'm running out of usernames due to the advice I give. Ha! Ha! Nah, just kidding, but do you see where I'm coming from?
I'll say this much; in my trying to think logically, since monitor cages should hold quite a bit of moisture and if dirt is used, it should be kept humid, I'd try to steer away from types of wood that tend to swell, whether I intended to fiberglass it, polyurethane it, or whatever. Every extra precautionary step you can take should be taken.
With that said, in the thread I mentioned earlier, someone stated that they had fiberglassed (I think that's what they used) particle board in a sav cage and it lasted for at least 7yrs that they know of. That's impressive to me. Even somewhat enticing. I can't argue against it. But that's not to say that someone else's caging conditions (inside & out) would decrease it or improve it. It definitely speaks volumes about fiberglass, though.
All the same, it's hard to argue against the use of metal stock tanks for holding dirt.
If you've read that thread I mentioned then you know about the cage I'm building. I've decided to either install FRP panels or fiberglass the plywood interior walls. That plywood, by the way, is 3/8" B/C grade, plain ol' plywood.
Savs climb trees but don't live in 'em. They live, spend most of their time, in burrows. That's why I feel that length & width is more important than height, within a reasonable degree, that is.
I hope this helps. I know it's not straight-out answers but it should still help.
Catch ya later!
HH
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Due to political correctness run amuck,
this ol' hillbilly is now referred to as an:
Appalachian American