Randy,
The rack/pinion on the quill is a weak point. I bought one at auction some years ago, then found replacement quills were not to be found. In fact, found a machinery dealer in Texas that had several with broken teeth in the rack. I was going to CNC it so didn't care. Until I learned that ballscrews for non-Bridgeport clone mills were expensive enough to make it not worth the effort. I was lucky, was able to hone the head slightly and adapt a Bridgeport quill. I frankly don't recall if the pinion was pressed onto it's shaft or if I machined it off. Shaft is tough, used up a keyseat cutter cutting the new keyseat. Though different pitches, amazingly, the Bridgeport pinion on the Induma shaft, came to the exact same quill/shaft distance as the original! The mill has been giving good service to a friend for 5 years now. In some respects, I like it more than a BP.
If the quill rack/pinion is in good shape, the leadscrews don't have excessive backlash, and you want it, take it!
Jon