AIE1
The jeep would have gone to DRMO with out the gun, so no, on the hard target just because it was a M151C model.
Remember, the gun and mount just rolled into the back of the jeep. I think it took 3 soldiers to put it in the back of the jeep. The back legs of the mount would then clamp it into place. The same mount would be used on the ground when not in the jeep.
I am building a M38A1C this summer. One of the "you got to be joking" parts in the manual on how to convert a M38A1 into M38A1C is, in the manual it shows you how to cut the tailgate out of the back of the jeep. You use a chisel and a hammer! I think I will be using the cutting wheel.
One more thing, it took me about 2 years to find all the parts to build a M38A1C. Be careful when buying the over load springs for the back of the jeep. I have seen for sell, but it will not be the complete kit needed. Make sure you are getting all the parts needed. The 106 was the easy part to find.
One of the few, Frank USMC RET