I've been there, with a Trek 930. Good times, almost as fun to convert as it was to ride.
You've got two easy options with the brakes...
1.) The brake bridges you mention are available at speedgoat
. Not sure how big a tire you can fit in there.
2.) Some adjustable height cantis have enough play to fit 700c wheels with the 26" wheel bosses. I used Avid tri-aligns... Onza's
are commonly available on ebay.
For the derailleurs, make sure that the cable routing matches your FD. Mine had cable stops for a top-pull front, so I used the Deore FD for a while. It worked just fine with bar-ends.