Thanks for The Adam Baldwin reference on Knots Landing.
Another one that wore super tight jeans was Scott Baio during the syndicated years of Charles In Charge. As the seasons progressed and Scott directed some of the syndicated episodes there, his jeans became tighter and tighter as the years went by. While he probably didn't have a big package, he did have a cute ass.
Another one was John Ritter in Three's A Company.
Anymore you can think of?