This subject or request appears to be showing up quite often, and there's plenty of information already available in the list archives if one searches for it.
Michael is right, that a conventional drop bolt must be modified in order to work when flipped or reversed (i.e., a spring slot or groove must be cut or filed). I had to do this with two (2) of my bikes, a contemporary Ron Cooper built Bates and a Rauler Tandem (Bates was spec'd to be equipped with vintage Campagnolo Record/Super Record sidelpulls, but fork was obviously built with shorter clearance).
Photos of my modified drop bolts may be viewed at the following Wool Jersey site addresses:
http://www.wooljersey.com/
http://www.wooljersey.com/
http://www.wooljersey.com/
I know that there is or was a drop bolt that already included the additional spring slot for reverse mounting. Seem to recall that it was made by Scott or Scott Matthauser??? I have one, but am too lazy to search it out to confirm.
I have also found that Modolo sidepulles provide a higher brake pad mounting range than Campagnolo sidepulls, so these should also be considered along with the already discussed Aero Compes. I tried a Modolo Professional brake on my Rauler tandem, and the pads could be adjusted high enough to correctly contact the rim sidewalls.
Forgot to mention that finding a conventional long nutted non-recessed drop bolt is next to impossible. Campy didn't make one, but Japanese copies were produced.
Happy New Year to all!
Kevin Kruger - Grantville, PA