was the german winter white equipment actually white or more of a gray color (or other)?

It was white, but for painting very light grey would work better. Otherwise you would have no highlight color.
http://www.dererstezug.com/winteranzug.htm

Depends. Early garments for camouflage only were white cotton. The Special Winter Padded clothing started white, but with wear quickly went yellow, to the extent it then became necessary to wear cotton camouflage over the top. This may have been partly due to the padding, which was reclaimed wool scraps etc. To try to reduce this, troops were told to wear the clothing mouse grey or camouflage side out when not actually in the front line.

I like to use Panzer Aces Stencil 313 or just splurge and buy PA 70.34

https://acrylicosvallejo.com/en/producto/hobby/panzer-aces-en/white-german-winter-tank-crew-70344/

Maybe Silvergrey 70.833 would work great too; that's what I use for all rank and insignias for German WW2.