I'm rehabbing an early/mid 80's Univega Gran Turismo for my girlfriend, and need to replace a few things (namely the rims/spokes and probably the brakes). But, naturally, I have a couple of questions first!

The bike came with 27" x 1 1/4" Araya single wall rims, but she'd like slightly narrower rims, something like Sun M13s. With cantis like the Tektro CR720, which I believe has a threaded post, could there be a potential problem with the pads hitting the rim off square? Like the top of the pad hitting the rim and keeping the bottom of the pad from engaging? The current Dia Compe 960 springs are in pretty bad shape, but they have the smooth posts that seem to offer a little more options for adjustment.

Here's some pics for reference:
Tektros:

Old Dia Compes:


I wrench quite a bit on my own bikes, but cantilevers are completely new ground for me, so any insight would be greatly appreciated.

Also, if this fits in better in the C&V forum, hopefully a mod will bump it over there.

Been a creeper for a while in the forums, but this is my first post. Thanks for the wealth of knowledge you guys have already put out there!

Z