Have just read this old posting and i just thought i would tell you why there were variations in colour of these "racing" 40s and 917s of JWA/GULF.
Lightness!In those days cellulose was used and in order to keep weight down very light, almost wash coats, were applied and thats why in many instances you could almost see right through bodywork when the light was right.If you ever get the chance to look at an original RACE shell you will see why none of us need ever fuss about whose body is best.Inside of some shells you will see narrow strips of carbon-fibre bonded to the thin, almost single laminate moulding to give lightweight rigidity!So do not get too worried about colour variation.
Regards,
GTA.