Thanks for the advice Kelly, now its time to design the pieces!

Does anyone happen to have photos or drawings for the variant of the throttle produced by Baldwin as discussed?

Thats definitely the plan Dave! Make a small locomotive that is capable of running distance without any issue. So far the list of improvements consists of rocking grates, a hopper ash pan, a very slightly larger boiler, a Porta exhaust nozzle, air brakes instead of steam, a welded shell boiler with a welded copper firebox (not 100% on the combination yet), copper side stays for flexibility, and a few other improvements here and there. We're closely following the Lyn project over in the UK to see how well their superheaters work on a 34" boiler, as were worried about space limitations relative to maintenance and longevity.

Then by all means go with the front end throttle - whatever superheat you can provide will only add to the efficiency and up there it will present no issues about making things fit - the smokebox of course can be designed to accommodate it, and a half-inch rod can fit under the tank. No packing gland required.......

Please if possible keep us informed on your progress - if it's a bit esoteric for this forum, the SteamTech Yahoo group would be perfect for it. I hope you are already working with Dr Koopmans and Mr Guy..... they have been very generous with assisting me in projects which start off enthusiastically and then never quite get off the ground. At least we have the intellectual exercise.