I would suggest using either the German 2-6(f) that came in PB (I think it was PB) or use a Hungarian 2-7. While having a good cyclic rate, up there with the MG 34 or MG 42, it used 75 round saddle drum magazines rather than a belt. As far as I know (so don't quote me on that) the barrel could not be changed quickly. Overall I feel that it was not as capable of sustained fire as the MG 34/42, closer to a DP-28 or Lewis, so I rate the FP as 2. It's high cyclic rate for short bursts means I judge it having a bit more 'reach', so I would be more inclined to a range of 7 rather than 6. The B11 for both is another matter. LW troops would have been above average in technical ability but at least for the first year were regarded as poor and skittish, so fumbling might be a
Overall a Hungarian 2-7 would be best, you can always SSR the B# to be B12, depending upon how you read an action.
The whole FP and range for MGs is so arbitrary and fuzzy that the best I can do is give a personal judgement rather than the more solid values I could give for an AFV.