Big haulers are really big
Well, yes. Very large for their scale, actually. Almost too wide for a narrow gauge engine.
This photo is a Big Hauler tender (1:22.5 scale) next to an Accucraft C-16 tender (1:20.3.) Notice the smaller scale tender is still physically wider.
I think the 1:20.3 scale tender looks quite good behind the big hauler:
To get back to the question, I have a Delton/Aristocraft C-16 (1:24th scale by the way, which is why it starts out looking small,) up-converted to 1:22.5 scale to match my Big Hauler(s). The tender is small, but I added larger trucks and it looks the right size - a model of a small tender.
Here's how it looks on a train of Big Hauler stuff - that gondola is instantly recognizable! The stack is taller (Big Hauler brass cap) and the cab is 1/2" higher, in addition to the tender trucks rasing it up 1/4".
If you are still interested, I can take a photo of the Delton tender behind the 4-6-0, but not until I get home next week.