Rory,
I can't tell you the white used on the plastic racers, but you probably can do some googling & online searching to find it & the Porsche name & color code for their race cars in "white". You might also try looking at the Colliers Museum article in Panorama or Excellence for their website, & see if they have any color name/code details on his collection of Porsche racers up to `73.
I think that Grand Prix White was a later color/code on production cars from the `70's on, but I may be wrong.
As for the L80e pic you saw - you probably saw a faded or off-color rendition (camera &/or screen) version of L80E if it was tan looking - as you can see from the pix above. Light Ivory is very hard to tell as being off-white, unless it's next to a truer white like the Grand Prix white cars in the pix above.
BTW - IIRC on the 914-6's the full Porsche color code was supposed to be 1110 for Light Ivory with black - for the targa roof/sails/rollbar & raockers/valances in black.
PS - You can see examples of 914s in various colors for each MY, if you click on the 914 color silhouettes under each MY to go to the car example.
http://p914.com/p914_paint.htm Tom
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