The stem would be easy, agreed and I looked at that. The legs could be extended by machining a small extender that threads in as long as the springer is the type that the risers thread into the top of the legs. I just wasn't sure I wanted to put that much stress on those two 1/2" bolts. I suppose you could machine the spacers for through bolts and use a grade 8 bolt.
By the way Pat, Ed made a girder as far as I know no one made a springer yet. I actually like a girder better with the "clutches" on the sides like a British one I have here.

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