Disc brake decision DONE..finally

the brackets are $105 + $16 shipping
check your local auto parts store for the price on 1990 Chevrolet Celebrity calipers and Toyota Previa rotors and 1979 to 1985 Cadillac Eldorado front hose, and an adjustable proportioning valve (or grab a used one from the junk yard) and a disk brake master cylinder for your application that will do the conversion
you may want to add new wheel bearings and seals while your at it