Spot on Midland 331, it was down to how long the power cable was as to whether the ground crew put the GPU to the front and had a shorter heave on the cable to gather it in and make sure you're clear of the props before leaving the safety of under the fuselage, or put it behind the wing, side on so that the propwash didn't blow the GPU over, and the ground crew were bathed in the hot exhaust fumes as the packed the heavy cable onto the GPU and drove clear.
The only aircraft I saw that had a worse position for the GPU lead was the Swearingen Metroliner which had the socket on the starboard engine nacelle midway between the props and the wing leading edge!! None of the engineers enjoyed this.