47-55.1 Requesting input on good fuel tank options (under bed)

[Brown Package]

By best I mean the relatively easy, and hopefully baffled design. I want the OE tank out of the cab, and a new tank under the bed. Nothing fancy mind you, but solid working tank. I have called a lot (but being new probably not most). So far Brothers, LMC, Speedway, CPP, and Tanks Inc. The others which are more "universal" are JEGS, and Summit.

I am leaning toward a 16 gal Tanks, or Brothers...especially since Brothers were so helpful on the phone....kinda feel like they would come help install it!

Anyhow given all the resources the reason I ask is the rear leafs are welded in pretty narrow at the rear from the previous owner. Not trying to be cheap, or put things off (unless necessary), but to pace the budget on everything you could do to one. Truck has a 12 bolt rear end, and V8 donor from a passenger car already. Things look rather tight, and I don't want to tub for wheels/ tank/ etc. again unless it becomes a "need". Thanks for helping a nub.

Rob