I would just order a 100 pack of 44s and be done with it.
http://www.cometpinball.com/product-p/100-pack-led-bullet.htm

26.00 bucks and you wont have to worry aboot them for long time. 25 pack is like 7.5 bucks and my ->guess<- would roughly 38-46 included the mezzanine or backbox.

NGG Looks best with Warm White Frosted or Sunlight.

GI is likely around 30-35 bulbs.

For your inserts, you can use Warm white across your Yellows, reds, and greens, as well as cool white, but color matching them will make them richer, and hide scratches.

If your choice is to add some green in the GI, like the others, just stay frosted.

Twin 2835 make the game jump, and Grab 4 Op Max for the back.

NGG is a dark game. I don't think putting colored LED's in for the GI is going to help you in that regard.

GI are 44/47 Bayonet Base.

For the backbox, just remove the backglass and count.

Fill the whole backbox with the same frosted...Sunlight or Warm.

You can then pull a bulb here or there, if you wish to save...in many cases its barely noticeable,
Adding any color in the backbox, is best tested with all the whites in, as there will be light bleeds from the color.

The Opmax is for the back of the game in the GI to light from below...the other choice is a backboard strip to light from the top down. If you get a strip, get a brightness screw, so you can tweak to your taste.

reach out to Ryan Wanger at Comet, hes likely jet lagged from PA, but any details, he can share.
If you want a pre made kit, or other choices, Pinside quality vendors also include Pinballbulbs, Nifty,
Cointaker, and Pinballlife.