Simple question for the cognoscenti. I have a '74 850 with the big ugly (IMO) rectangular stop/tail light. All pattern parts so no "originality" issues. I'd like to swap it over for the earlier Lucas 697 "Beehive" type on the stock mounting. Bearing in mind the vagaries of fit with pattern parts, should the mounting holes in the rear fender the same? Any traps to be wary of?