lighthorseman,
I can give you a few dimensions which may help.
skid length= 14'-15'
skids=12" X 12"
boiler diameter=39" - 42"
boiler height (to top of stack)=12'
boiler height to beginning of taper to stack=7'
boiler, winches,etc are mounted on 12" I beams bolted to skid
stack diameter=9"
These dimensions are close, there were different manufacturers, so sizes varied somewhat, but this should get you, not just in the ball park, but within the base lines.
Pete