I just finished a somewhat-customized version of the Backwoods Engine Shack for my On30 mini-layout. It was a lot of work but I think it was well worth the effort. Pictures and build notes are on my blog: https://lockwoodandsanemigdio.blogspot.com/2023/03/enginehouse.html.

I found this kit great for customizing as well. I shortened the building and raised it to fit my Thomas The Train custom engine built on an American Flyer handcar chassis.

Hi Larry, Do remember how you positioned the rafters so they lined up with the gables on the front and mid walls? Many thanks for posting your photos on line!!! Sam

As I recall, I made a jig. Printed an extra side wall, cut out the rafter slots at the top, then inverted it and used it at the top of the rafters to hold them in alignment.