Hi Ben,
p.s.
You may find this interesting. It is part of a 16th century Sanskrit text written by a sage called Purnananda Swami, where he describes part of the subtle nervous system in the pelvic region. As you can see, he also mentions many different colours in just one part of the subtle body.
Verse 1
In the space outside the Meru, placed on the left and the right, are the two Siras, Sasi and Mihira. The Nadi Sushumna, whose substance is the threefold Gunas, is in the middle. She is the form of Moon, Sun, and Fire; Her body, a string of blooming Dhatura flowers, extends to the middle of the Kanda to the Head, and the Vajra inside Her extends, shining, from the Medhra to the Head.
Verse 2
Inside her is Citrini, who is lustrous with the lustre of the Pranava and attainable in Yoga by Yogis. She (Citrini) is subtle as a spider’s thread, and pierces all the Lotuses which are placed within the backbone, and is pure intelligence. She (Citrini) is beautiful by reason of these (Lotuses) which are strung on her. Inside her (Citrini) is the Brahmanadi, which extends from the orifice of the month of Hara to the place beyond, where Adi-deva is.
Verse 3
She is beautiful like a chain of lightning and fine like a (lotus) fibre, and shines in the minds of sages. She is extremely subtle; the awakener of pure knowledge; the embodiment of all Bliss, whose true nature is pure Consciousness. The Brahma-dvara shines in her mouth. This place in the entrance to the region sprinkled by ambrosia, and is called the Knot, as also the mouth of Sushumna
Verse 4
Next we come to the Adhara Lotus. It is attached to the mouth of the Sushumna, and is placed below the genitals and above the anus. It has four petals of crimson hue. Its head (mouth) hangs downwards. On its petals are the four letters from Va to Sa, of the shining colour of gold.
Verse 5
In this (Lotus) is the square region (Cakra) of Prithivi, surrounded by eight shining spears. It is of a shining yellow colour and beautiful like lightening, as is also the Bija of Dhara which is within.
Verse 6
Ornamented with four arms and mounted on the King of Elephants, He carries on his lap the child Creator, resplendent like the young Sun, who has four lustrous arms, and the wealth of whose lotus-face is four-fold
Verse 7
Here dwells the Devi Dakini by name; her four arms shine with beauty, and her eyes are brilliant red. She is resplendent like the lustre of many Suns rising at one and the same time. She is the carrier of the revelation of the ever-pure Intelligence.
Verse 8
Near the mouth of the Nadi called Vajra, and in the pericap (of the Adhara Lotus), there constantly shines the beautifully luminous and soft, lightening-like triangle which is Karmarupa, and known as Traipura. There is always and everywhere the Vayu called Kandarpa, who is of a deeper red than the Bandhujiva flower, and is the Lord of Beings and resplendent like ten million Suns.
Verse 9
Inside it (the triangle) is Svayambhhu in His Linga-form, beautiful like molten gold, with His head downwards. He is revealed by Knowledge and Meditation, and is of the shape and colour of a new leaf. As the cool rays of lightening and of the full moon charm, so does His beauty. The Deva who resides happily here as in Kasi is in forms like a whirlpool.
Verses 10-11
Over it shines the sleeping Kundalini, fine as the fibre of the lotus-stalk. She is the world-bewilderer, gently covering the mouth of Brahma-dvara by Her own. Like the spiral of the conch-shell, Her shining snake-like form goes three and a half times round Siva, and Her lustre is as that of a strong flash of young strong lightning. Her sweet murmur is like the indistinct hum of swarms of love-mad bees. She produces melodious poetry and Bandha and all other compositions in prose or verse in sequence or otherwise in Samskrita, Prakrita and other languages. It is she who maintains all beings of the world by means of inspiration and expiration, and shines in the cavity of the root (Mula) Lotus like a chain of brilliant lights.
Verse 12
Within it reigns dominant Para, the Sri-Paramesvari, the Awakener of eternal knowledge. She is the Omnipotent Kala who is wonderfully skilful to create, and is subtler than the subtlest. She is the receptacle of that continuous stream of ambrosia which flows from the Eternal Bliss. By Her radiance it is that the whole of this Universe and this Cauldron is illumined.
Verse 13
By meditating thus on Her who shines within the Mula-Chakra, with the lustre of ten million suns, a man becomes Lord of speech and King among men, and an Adept in all kinds of learning. He becomes ever free from all diseases, and his inmost Spirit becomes full of great gladness. Pure of disposition by his deep and musical words, he serves the foremost of the Devas.
Verse 14
There is another Lotus placed inside the Sushumna at the root of the genitals, of a beautiful vermilion colour. On its six petals are the letters from Ba to Puramdara, with the Bindu superposed, of the shining colour of lightning.