Since they are Lucas, they are compatable with the dim and flicker mode of the Lucas switches. Not sure if they come with the proper polarity smoke. They may contain positive earth smoke, so be mindfull of polarity when wiring
Now, on with the seriousness. All Lucas 488 lamps are relatively flat lensed ones. They are common in clear, red and amber colors. I see that they were also available as side marker lights with frosted clear glass too. They are exactly the same internals, trim ring and rubber as the Beehive lamps (Lucas 594), just different lenses. See this link for a reference 3/4 view photo:
http://www.triple-c.com/Products_and_Accessories.cfm?pn=L488&pID=271 Note the statement that current production Lucas lenses are glass but colored lenses are painted on the inside. Should not be an issue for backup lamps.
Both the 488 and 594 assy's are available for use with either single filament or double fillament bulbs, 1156 & 1157 respectively. So watch what you buy.
I believe there are copy units that may be less expensive but may come with plastic lenses.
My research shows these may have been used on Metropolitans. Maybe one of the Met builders might have a spare set?
If you decide that you'd rather have the 594 style Beehive lenses, and can't find anything but the 488's, I may have a couple glass lenses up in storage. Let me know.
_________________
Chuck.
“Any suspension will work if you don’t let it.” - Colin Chapman
Visit my ongoing MGB Rustoration log:
over HEREOr my Wankel powered Locost log :
over HEREAnd don't forget my Cushman Truckster resto Locostusa.com/forums/viewtopic.php?f=36&t=17766