This photo is from the 1959 Better Homes and Gardens Holiday Cookbook for St. Patrick's Day.
I don't know about that meat, not perhaps the most appetizing presentation, even with the pipes in the potatoes. A suggestion is made for Horseradish Sauce:
"It's a spunky accent for corned beef; another time for pot roast. Soften one 8-oz. package cream cheese and fluff it with electric mixer. (Fluff it?) Beat in 2-3 tablespoons of prepared horseradish. (Um, that's it? How do you do that?)"
Cream cheese must have been the ultimate delicacy in this time period; those sandwich loaves are covered in it.
Oddly enough, green beer is never mentioned in these books...