I assume that by "M42" you mean "Truck, 3/4 ton, 4x4 Utility, M42",
-not- "Tank, Flame Thrower, M42".
TM 11-284, May 1953, indicates that the correct radio for the truck
could be a Radio Set AN/GRC-3,-4,-5,-6,-7, or -8. I say COULD because
I'm sure that Radio Set AN/VRC-8,-9, or -10, or Radio Set
AN/VRC-16,-17,-18,-20,-21, or -22 would also be correct but I do not
have direct documentary evidence to substantiate this.
The primary difference in all of these sets is in the frequency ranges
covered, and the quantity of modular receiver-transmitters and auxillary
receivers with which each variation was equipped.
As a starting point, the band 20 MHz to 27.9 MHz was designated for
armored forces use, 27 MHz to 38.9 MHz was designated for artillery use,
and 38 MHz to 54.9 MHz was designated for infantry use. Info per TM
11-284.
You need to decide which army force you want to equip your vehicle for,
then decide whether you want a "large" (GRC-3 thru -8), "medium" (VRC-16
thru -22), or "small" (VRC-8 thru -10) configuration radio set. Hint:
unless you are really into radios, I suggest you choose a "small"
AN/VRC-8,-9, or -10. The entire family of radios discussed here was
designed in the late '40s and manufactured from '50 to around '56. The
stuff is all vacuum tube equipped and is relatively unreliable compared
to modern solid-state equipment. If you go for a larger configuration
set, you may find yourself spending more time and money keeping the
radio equipment working than you do keeping your vehicle running!
If I can be of further assistance, just holler.
Regards,
Ed Greeley
Mobile, AL