I thought for sure my Dads Custom Royal blew it's engine but he said no. So much oil smoke it was crazy. But he took it in to a garage and they cleaned the top side of the heads under the valve covers and blew out the oil return passages and all was well again. No more smoke.
Different engine than the Custom Lancer I believe, it was non hemi, Something on the order of 320 ci, 4bbl carb and dual exhaust. I remember it had a heck of a hole shot from traffic lights. Impressive for such a big car.