When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Yeah, in the third position, "P" is for 62 and up Motorcraft/Autolite. An "H" is for 66-82 Heavy duty trucks and 83 and up medium duty trucks. Hope this is what your lookin' for.
I think (I know-that will only get me in trouble!) the m/a desination is for any part that was jointly developed/labled, such as carbs, filters, plugs ect., for these it would be more of a ID # that would indicate it is indeed an autolite part that was "incorporated" and designed for/by Ford. Maybe someone else can help with a little more. Have a good one!