Looking good Bill !
Too early for my layout, but I'm seriously thinking about one for the display cabinet.
For me, none of the 'faults' pointed out would be deal breakers. It still looks like a Stirling Single to me. If they can be corrected, great. If not, I'd live with them. It's also worth bearing in mind that the pictures on a computer screen are about 5 times larger than the model will be at 1:76.
Having said that, if some of the concerns can be addressed, could I suggest that the cab windows look a tad small compared to the prototype in the comparison pics posted previously.