Hello All,
Here are examples of locomotives with lighter colored boilers, compared to the cab and tender in B/W... Clearly, one can see these boilers are not black using the method from utah rails....
Here is #3601 2-8-8-2, in B/W with a green boiler
Another Great example using the famous DM&IR 2-10-4's that had Grey boilers, and black steam and sand domes, and black cab and tenders... You can see the lighter grey boiler. Again, using the same method as Utahrails, and the formula holds true...
With that being said, we all know how rare color photos of L-105s are... But with this method we are able to determine which ones had a Green boiler. We owe it to the history of the D&RGW to depict the engines that kept their green boilers, to truly and accurately depict these engines in all their glory and Beauty.
Here is #3703 in 1949 at Soldier Summit, shot by Otto Perry. Look at the boiler vs the cab and tender which are black. You can see the boiler is clearly lighter than the black of the cab and the tender. Also, boiler is lighter than the Elesco, Pilot, steam and sand domes, which we know were black... this proves this engine was green boilered in 1949!
This means we have at least #3700 , #3703 and #3705 for a possible 6th version L-105 4-6-6-4- postwar Green boiler with overfire jets for Sunset 3rd Rail to Produce! 
Here is a 1948 Slide of #3700, note the Green Boiler - both pictures taken at same location at Grand Junction, CO
