Scott,
Good question. Having been there at the time and being the painters assistant during my first tenure there; I never gave it a socond thought. I decaled lots of Masis and there were thousands of 531 decals just sitting there. We never used a single one and I didn't think to ask why at the time. The answer would probably been "because" anyway; but it just never came up. We weren't there to ask questions anyway, we were there to work and do as we were instructed; and to learn. Also sitting there at the time were thousands of the "Nervex Professional" lug decals which weren't used either. That I assumed was on account of the fact that we were using the DuBois Nervex lug at the time. My 1962 Masi Special on the other hand does have the Nervex lug decal on it in addition to the Reynolds 531 "frame tubes" (meaning main triangle tubes) decal. Go figure.
Brian Baylis
La Mesa, CA