@asctim: Drums is my main instrument.
I've personally known only one bassist who went from electric to acoustic upright bass: Todd Phillips, who has worked with a lot of the modern Bluegrass masters. Tony Rice, Jerry Douglas, David Grisman, etc. In 1971 he was playing a Fender P Bass in a band he was leaving just as I was entering. He did so to concentrate on learning mandolin, so went up to Marin to study with Grisman. David told Todd there were already a lot of great mandolin players, but a dearth of upright bassists. Todd took his advice, got himself an upright, and has been working steady ever since.
The one guy I know of who played (R.I.P.) a non-upright electric fretless bass (an Ampeg) was Rick Danko of The Band. Rick is one of my favorite musicians. And one player who makes his fretted electric bass sound uncannily like an upright is Joey Spampinato of NRBQ. He is another of my favorite players, and is Keith Richard's favorite bassist. When Bill Wyman left The Stones Keith offered him the job, and Joey turned him down! But he did agree to play in the band Richards assembled to back Chuck Berry in the Hail! Hail! Rock'n' Roll documentary on Chuck.