I'm not a steam guy by any stretch of the imagination, but it seems to me that adding another axle to the pilot means stretching the frame forward to accomodate it, which means stretching the boiler as well for proportionality, which in turn would cause your loco to no longer look like what you were planning in the first place. Of course, like I said, I'm not a steam guy, so I could be waaaaaay off here.
Mark
I wanted to convert my Scientific Toys "Walter E. Disney" from a 2-6-0 mogul to a 4-6-0 ten wheeler. I've been struggling a lot with it and starting to think that its frame is not intended to be a ten wheeler. I've made her more authentic with a ballon diamond stack, matching brake pump, re-painted drive wheels and pilot wheels, and it seems that all it needs is a 4 pilot wheel arrangement, to bad that the sand dome and bell can't be switched for sure. I'll post photos later so those of you to see how much closer she looks to Walter than how it was made originally.
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