This can be done. I have seen sites where the calipers were clamped in position and could be removed for hand use. There are also "quill kits" that are single axis dros. these look like calipers with mounting hardware instead of jaws. There is even a remote readout that will make it look just like a regular DRO. Some will interface with a cheap laptop for the readout, like here:
Search ebay or Google for quill kit.
Ron Thompson On the Beautiful Florida Space Coast, right beside the Kennedy Space Center, USA
The link below is a good place to start, the ShumaTech readout is a DRO kit that was designed to interface with digital caliper output. There are links there to other similar sites with pictures of mounting methods and such.
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