A good place to start is Carlos Llamas' shop photos:
[
grande.smittyshouse.net]
You may have to dig, but I've found some nice shop photos of the steam dome, throttle and stay bolts on Carlos' site.
Another good source which I've posted the link to before:
[
modelsteamengines.tripod.com]
The elevation and section cards may be helpful, and the boiler drawing should help with the stay bolts. Costs money though...
Great stuff here as well, may have what you're looking for:
[
theironhorse.blogspot.com]
Wish this guy would publish his work...
Mike