Columbus SL tubing, purchased from Colorado Cyclist in 87 or so. I would use straight mtn bike handlbar and 2finger bmx brake levers (the $4 from nycbikes). The brake calipers are shimano 105 from about 87. Do you think I will be able to run tires similar to Specialized Houfallize CX or Borough CX 700X32X (ie will there be enough clearance in the brakes?). Thanks!