Thank you for your kind replays and likes. 
And yes I will update the progress of the rebuild and painting process.
Concerning the question what I used for tools? The only thing I used so far was a broad X-acto Extra fine saw blade. Sanding was done with two different grits of sand papper.
The options of lightning in the dome I suppose it's correct to have it both ways. From below and above even in the pre 1960 domes. Even if the lightning from bellow was the most used when the train was in motion.
And here is the Dome area today from the WP Silver Crescent at the Gold Coast Railroad Museum.
Figures will be mix of sizes. In the dome I will use as "big" figures as possibly. Figures From Slaters and Golden Gate depot is what I'm currently test fitting. In other areas I will go for Preiser and some Chinese made figures that I got of eBay. The Chinese figures seams to be copys of Preiser's. The Slater's and Golden Gate is closer to S-scale then O. In the picture below, the white and painted figures is from Preiser and the tan ones is Chinese.
The smaller Slaters figures is primed black. There is different schools to paint figures. Nowadays I start with a black base and go lighter avoiding to paint in "shadow" areas.
