Congratulations on 50 years of wedded bliss, but you are still on probation.
I have almost made 50 years of marriage, but it took 3 wives. The engineering degree from U of Wisconsin didn't take 50 years, but at the time it seemed like an eternity. Finally graduated with a BS-Mechanical Engineering at age 31 after the air force, and received my PE license from the state of Wisconsin after 4 years of engineering employment.
I maintained my PE license, in Wisconsin and Georgia, for about 25 years. At the end, I had made a total of $250 from that license for reviewing one design for a lifting fixture. I think it helped me get a couple of new jobs following lay-offs, but never rang home the big $$$. The personal satisfaction was priceless.
Kudo's to you... Took me 4 wives, and Amy 3 husbands. Been together 34 years now and still best friends. Like 2 book ends. I tell people I'm 'Henry the 7th (Herman's Hermits, Henry the 8th...lol) minus 1. I guess practice makes perfect.