New England Steam is on the search for plans Maine Central 470's tender trucks and brake arrangement.

1. We believe she has Commonwealth Four Wheel Tender Truck, but her model differs slightly from the drawing we are able to locate.
   
   The illustrations found to date show a slightly different version from the same era. Figure 1 shows the illustration in the 1922 Locomotive Cyclopedia (left) and 470's from 1924 (right).
   
   Can anyone identify the exact model we have and/or know the location where we might find drawings? Any identification of the type of brake system used by 470's tender trucks?
   
   Figure 2 is a Barber Equalized Tender Truck that seems to be just as similar as the Commonwealth. This is plausible, but due to the fact 470 has a Commonwealth Tender Frame, it would be assumed American Locomotive would go with the same manufacturer for the trucks
   
   
   Figure 1
   
   
   Figure 2
   
   
   
2. We are also looking to find the identification of, and any drawings applicable to the tender brake rigging. The drawings found to date show the "live" (the side of the brake linkage on the truck that is connected to the rod from the brake cylinder) portion of the linkage on the outside of the trucks with the "dead"(side of linkage that is connected to the "live" portion) portion on the inside. Figure 3 shows this arrangement.
   
   470's is reversed. The "live" portion is on the cylinder side, and the "dead" portion on the outside. Figure 4 is of truck #2 taken from the cylinder side looking aft.
   
   We need drawings of the brake linkage as we are rebuilding it. While this is not difficult to draw, I have not seen any documentation or drawings of this. Any thoughts on this arrangement? Leads on plans? What is the name of this type of tender brake?
   
   
   Figure 3
   
   
   Figure 4

This is probably not useful at all, but one thing I found is that it looks like NYC was ordering these same tender trucks on its earlier Alco 4-6-2s. No one else was, even MEC on its order of 4-6-2s prior to yours (edit: it looks like IC ordered them too). Not sure if any detailed drawings survive anywhere, or a whole locomotive, but NYC had so many of these and was a much larger company.

https://www.railarchive.net/alcopacifics/

Here is a photo that shows the brake cylinder, though the truck design is a bit different from yours:

Are you sure the trucks are Commonwealth and not actually Barbers? I see several things that point to Barber: The Commonwealths are one-piece frame castings while the Barbers clearly have the same bolted-in transom casting construction as in Figure 1764 (along with the bolts through the frame sides) as your trucks, the Barber drawing has the same 1/2"x6" drop straps from transom tops under the spring plank as yours, and the leaf spring groups are farther inboard (don't protrude outside the sideframes) than the Commonwealths. I'd be looking for Barber drawings first.

It had slipped my mind that the original specs sent to ALCO in '24 for 470 were located and digitized.

Unfortunately the picture of them isn't great, but the tender truck section does provide information.

Can't find any photos confirming the style of USRA Standard Equalized Tender Truck