Gday Ralph!
To the best of my knowledge the duckbills were not used until the record wet weather of September onwards necessitated their use... As you probably know Operation Cobra was a high speed breakout in the good weather of mid July...
As for the accuracy, well it is one of the best OOTB... Removal is needed of the 2 fuel filler caps inside the splash ring surrounding the rear armoured cover behind the turret... They were (75) leftovers IIRC...
There is also the same problem as with the M4A3(76)W kit, in that the rear spare tracklink holders have hollowed sides whereas they should be blanked off...
Some extra casting should be added to the lower hullsides, and some scarring on the join of the turret halves... No muzzle brake should be used.
That's all I can think of right now...
I have a great pic of 'Elowee' in action (one of the decal options) drop me a PM if you'd like it
Cheers
Brad