Yes there was,,,, the T-19 HMC(M-3 Chassis)had a 105 howitzer, and the T-30 HMC, had the airborne version of the 75mm field howitzer..
There was also the T-12, 75mm (LONG) used for anti-tank..
(from Steven Zaloga's "US halftracks of WWII", pg 33-40) Tanks illustrated #15
Personally I'll like to see a T-28e1, (africa) with the twin water-cooled 50's and a 37mm, or the aircooled 50's ands 37 mm of the M-15.
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GreyBeard, Squadron Leader
Commander, "E" Flight, Aces High
Senior Staff Council
"The Skeleton Crew"
"Fly with Honor"[/i]
"Keepin' the Faith"