Over the years I've replaced the plug in my Duraforce (E series) mower with the recommended NGK BPMR4A setting the gap at 0.035 in. (0.90 mm) as specified on page 15 of the Operator's Manual. Well, while looking at the Service Manual today on pages 2 and 14 it specifies 0.030 in. (0.76 mm). Does...