Joe, glad you could join us!
Most of the disc conversion kits are in the $600 range. If you buy at a major swap meet like Carlisle, they often give a price break, or throw in goodies like a line kit.
If you want to use the stock 14" wheels, they may not fit with the discs. Scarebird offers caliper brackets that bolt to the stock drum spindles, use readily avail rotors/calipers, and will fit the stock 14" wheel.
I went back and forth on the disk conversion on my silver 66...I put the disc spindles on, then decided I wanted 100% stock, and now have to take them back off! The discs will go on my red 66 tho.