MTH PS3 steamer board use?

I got another board set from here on the forum from this engine:

http://mthtrains.com/11-6056-1

It just tested out great using a small MTH steamer (Atlantic). It was locked in forward but took a reset.

So I have several prospects to use it in. I have a Weaver PRR M1 2 rail. That would slip if drawn down by a big train as it doesn't have the rubber tires. It has a good sized motor though.

https://ogrforum.com/t...-steamer-2-or-3-rail

I'm not sure what the "lighter" boiler board can handle? I bought a heavier version to use inside my Allegheny when I upgraded it for safety.

I started converting this Weaver several times. Each time I stole the board set for another project. ( 3rd Rail Niagara, G scale steamer, etc.)

I could just use it in another smaller MTH steamer. I have a 2-8-0 that needs a board and 2 different 2-4-x's also. Those 3 rails also have single large can motors inside that look as big? The tires make me wonder about current draw? The tender main board probably is too big for the Atlantic tender anyways. 

So that makes me wonder what engines or motor size determine when to use the heavier boiler board with PS3? Is there a certain current draw to check for?

(motor stall?)

Can the small RK PS3 boiler board handle the Weaver's can motor?