1badgmc
+1y
You're talking about '87-'90 Caprice headlights. I have seen a truck that had them, but you have to cut out a lot of the headlight bezel for them to fit and they look kind of funky since they're so much bigger than the parking lamps.
If I ever get around to getting the update done on one of my '80's projects, I plan to get '90-'91 Celebrity Eurosport headlights. They're a bit smaller all around than the Caprice lights so they won't look as odd compared to the parking lamps. I've taken measurements before, and they should fit in the bezel with minimal trimming.