Once you start changing enough bits it is sometimes easier to start with a different bike.
The french BB thread might be awkward to retap (taps can break in the process) :
British 1.370" x 24F tpi left / right
French 35mm x 1mm right/ right
Some tandems have other strange quirks:
http://www.yellowjersey.org/bart.html
Also the Peugeot frames are commonly metric size tubes, strange size seat posts and front mech sizes needed. Plus, headsets that convince most people to abandon and get a different bike.