I am partway through building a Simplex and at the point of building the boiler. I have just found out that I have a breathing condition that may stop me running my loco on coal because of the smoke. Is it possible to fire it with gas burners? I am leaving the boiler while I investigate this as it may be the firebox or tubes may need a redesign. Has anyone any experience of doing this especially on a simplex or similar. I gather many locos in America are gas fired. Any ideas and especially any plans gratefully received.