i have the kit of our beloved revell, only that the painting instructions are tottaly useless!!! I want to build the U-216 version... is there any good lad who can enlighten me regarding which colours I should use?! I cannot make anything out of this...
Thanks!!

the majority of Uboots were painted schartzgrau on the bottom and lichtgrau on the upper surfaces. The deck was kind of an inbetween gray (I use Testors MM medium gray)

Some had schwartzgrau stipes or patterns on the upper surface.

As a probable alternative, metal portions of the deck were painted dark grey, or black. The wooden decking was always painted with a wood preservative which, when new, was black, but quickly weathered to a charcoal gray. Further weathering rendered it a brownish-dark grey color due to the wood beneath. However, since you are modelling a particular U Boat, you should stick as close as possible to the original color scheme, if you have that reference, as U Boats, even within the same flottilla, varied their colors.