My USMC manual "Painting & Registration Marking of USMC Tactical & Combat Equipment" MCO P4750.3 dated NOV 5 1964 says:
Semigloss enamel FSN 8010-526-1609 can be used as a one coat paint system and as a two coat applicaton. It may also be used as primer. Spec TT-E-485
Lusterless Enamel FSN 8010-526-1612 lusterless alkyd enamel used as exterior camoflague finish coat over primed metal. Spec TT-E-257
Then it says at the bottom:
Marine Corps green GLOSS (I made it capitalized - it says gloss not semi gloss) will not
be used on tactical and combat equipment.
It says interior paint should be white fire retardent paint 8010-286-7840.
Interior walls and ceilings of vans and enclosures with lighting should be painted semigloss enamel. Cab interior and deck machinery of cranes and crane shovels will be painted light gray number 26492 as listed in FS number 595 8010-616-0005.
Radoes used with radar or other electornics equipment will be painted olive drab semigloss enamel number 24987 spec TT-E-529.
And, it says that if you wanna paint something a way other than above you gotta ask the Commandant of the Marine Corps for permission.
#'s are assigned to all wheeled tracked towed less towed artillery, self propelled artillery...
USMC & numbers should be on 1 line whenever practicable.
They should be applied uniformly to each side.
Markings should be uniformly applied using letters 2, 3, 4, or 5 inches in height. The use of the largest size practicable in the available space will be the determining factor in letter and numeral dimensions.
Letters are to be close-spaced but groups of letters will be seperated from groups of numerals.
Equipment painted with USMC green enamels should be marked with yellow semigloss enamel or lusterless yellow enamel AS APPROPRIATE
Painted markings should be paplied through USMC stencils to provide a uniform apperance. Gumbacked paper stencils may be used since they adhere well to almost any surface and prevent paint from being sprayed or brushed under the edges of the letters and numerals.
Use of locally procured self adhering letters and #'s is authorized provided they are procured under spec MIL-D-8634 <-- I will try and find this...
Equipment in 24052 should be marked with semigloss enamel 23538 FS# 595
Equipment in 34052 should be marked with 33538 FS# 595
Should those not be available, use of a suitable substitute is authorized as a temporary measure.
Also worth mentioning is that there are pics of M38A1's, M422's, and even 60" searchlights in this book.
Another thing worth noting is that I can make you almost 100% correct vinyl decals for your mighty mites in yellow, or if you prefer to spray it on in paint mask. These are the non-stenciled numbers that you've probably seen in most pictures of M422's. You can see a picture of the same style numerals here (in this case I made them for a DUKW).
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