I have a twenty year old delta tub spout with separate water handles. We remodeled the shower stall, that sits on the garden tub edge, with a glass enclosure. We bumped out the glass wall to give a small ledge. Now glass is too close to old delta knob handle. I want to replace handle with delta stainless steel knob (windmill like). Can I move the hole slightly to allow for installation and operation? I don't have access inside the tub structure to disassemble the rough piping. Can I use a Dremel to enlarge hole? I only need half an inch. Will the rough piping have enough play? If I can, how do I fill the space I create behind the vertical threaded handle pipe?

Will the rough piping have enough play?
Not likely.

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