I'm completely lost why you think spaceships can't be colors.
Although the instrux quote the wrong colors anyway.
The 1701-D is very pale blue (I use RLM76) with a very pale green aztec pattern (but at that scale I skip the green pattern).
The 1701-A is overall white.
The original series 1701 is light ghost gray.
Best to drop in at the CultTVMan bboards at http://www.hobbytalk.com/bbs1/forumdisplay.php?f=15 and ask your questions. There are a boatload of Trek experts there :).