I am engaged in a discussion elsewhere online regarding PRR Steam boilers and would like to pose this question if I may...It has been said that the boilers of K class and L class locomotives are quite similar if not identical due to PRR wanting an interchangeable set of driving wheels/valve gear should any situation arise or something of that matter. Now with this in mind would it also be safe to say that the boilers of E6 classes and Gs classes be the same? We are discussing the progress of PRR 460 and the eventual (hopeful) restoration of LIRR 39. They LOOK like they are of the same dimensions but is this the case here?
In an unrelated (somewhat) topic, we also brought up...(sigh...) K-4's 1361 and talked about how Steamtown won the contract bid. Yeah, I know I know, its been beaten to death in here but would anyone have any literature on how the bidding came about or where I can read more on it? Looking for specifically JUST info on how they scripted the contract for the biding, procedures, potential clients (we all know the eventual client) and scope of procedure.
Any help would be much appreciated.
Thanks!!

Going from memory here, the boilers of the E6s, G5s and H8,9,10 were all very similar, to the point of having nearly identical critical dimensions like grate area and heating surface. However none of these were truly interchangeable. The E6s and H-class boilers (same boiler used for three different locomotives, each subsequently numbered series having cylinders 1 inch larger than the next) were nearly identical in both design and construction. The G5s class, though dimensionally similar was constructed very differently. The defining difference between the two types of boiler lies in how the outer firebox shell is joined to the boiler barrel. In the E and H class boilers, the rear barrel course, outside throat sheet and "hip sheet" (the distinctive transition piece from the round barrel to the flat top Belpaire shell) are three separate sheets all adjoining the rest of the firebox shell. On the G class boiler, the rear barrel course is actually two halves connected together with two longitudinal seams running along the course on the horizontal centerline. These halves are so constructed that the lower half has the throat sheet forged as an integral part and the upper half has the hips formed into the sheet. This construction technique was duplicated from the earlier k4 and L1 boilers.

As far as I know this (the 1361 project) was not a bid contract. Altoona paid a fee to Steamtown to cover shop skills management, and paid time and material when the NPS people worked on the project. They also hired their own employees to perform work under the direction of a Steamtown manager. The University of Scranton also played a role in the business end of the project management. After a period of time went by, Altoona hired a contractor to manage the project using Steamtown's facility, but not its manager, and also hired several more employees whose sole duty was to work on the 1361. The initial scope of work was miniscule compared to the task at hand, and the funding matched the initial scope of work. There in lies the first pitfall of the project. The rest is history.
Mike Tillger