1970 CST/20 disk brake and box upgrade?

[CSMMunguia]

Hello, I recently bought a 1970 CST/20 fleet side long bed original truck which has air conditioning, front and rear stabilizers, lead springs in the rear, power drum breaks, power steering and 400 big block engine. I'm contemplating the idea of upgrading my front suspension to a system which has disk brakes from a 1972 donor truck. Also, the bed has some damage on the driver side, the tail light corners and saddle tank access doors cut into the bed sides. I bought a pretty clean long bed box from a 1972 GMC sierra with saddle tanks that fill from the rear wheel wells. The GMC box also has both top moldings and lower moldings with simulated wood grain with a wood floor like the original box. I like the idea of eliminating the saddle tank doors since it will have a cleaner look and plan to keep it as stock as possible. Can any one tell me, If I go through with these upgrades, would the value of the truck be diminished?