Just scanned this, and somethings pop to mind:
- good choice getting solid wheels built.
- not so convinced about the suspension forks, despite them looking fairly beefy; have you checked rider weight limits and suitability for a tandem?
- if you keep to the original fork, I'm certain you will struggle with any mini-V due to the very short distance between the
bosses and wide rims*. I would recommend the BR-CX50 or BR-CX70 if you go modern with the original fork, or dig
out some older cantis like BR-M550 with upgraded 70/72mm cartridge pads.
Good luck with it! Looks fun!
* I'm actually wrestling with this at the moment........driving me nuts.