I dunno….I have about 130 motors that I have been collecting since back in the 1970s, and I don’t have one with a shield….Good running, nice sounding motors that will literally run circles around a TD20 Johnson.
A Shield Mark 5 was displayed at Vulcanmaster meet several years ago. It was pointed out to me as an unusual variation so photos taken. You never know what will show up at a meet.
I own one of those Mercs with the shield. I had to do some digging in the shed to take a picture. My motors all have covers and are all sleeping soundly! I thought I had a finished picture on file but could not locate it.