Gerald,
Six pounder guns, 12 pounder field howitzers, 10 pounder Parrotts, and 3 inch ordnance rifles were mounted on Type One Field carriages. 12 pounder Napoleons and 20 pounder Parrots were mounted on Type Two Field Carriages. The width from the faces of the rim bases Where the trunnion extends from the tube) required a wider carriage. I don't think the cheek and trunnion plates were taller. I may be wrong. It would seem that they would have to be. I'm sure Ron Black can give you (and me) more info. There was a type Three Carriage as well for heavier seige guns. The dimension on a six pounder from the center of the trunnion to the ground is 44.5 inches. (On mine anyway) Gun carriages and most rolling stock used 57 inch wheels. So the center of the axle was the same from type to type. Hubs and spokes and fellies (the wooden sections of wheels) could vary in beefiness. But the iron tire was 57 inches. Hope this helps.

Keith