Top 5 A-body mods...

No, not the first five steps, your top 5. Stuff thats out of the normal. It's pretty well established the proper steps of building a solid, safe, reliable, punchy A-body.
I'm talking about the things that every time you get in the car, you think, "so glad I did that".
Could be a stereo for some, recovering some tired seats, or mounting the same style dash compass you had in highschool, etc. The hydraulic hood/trunk lifts is a perfect example

on my '72 Valiant, she had 9" drums...so upgrading to BBP and discs was a no brainer. Can't worry about going, if you are worrying about stopping!
That said, I replaced the windshield washer system with a complete NOS system I bought local, right after I installed a fresh windshield. I used to get a big grin every time I mashed that foot pump and had a nice spray of Rain-X on a crystal clear windshield. Beaded water so well that I rarely, if ever, used the wipers. That was in Tacoma too. Another one was replacing the glove box liner, just so I could store the re-pop owners manual, and the mint ORIGINAL glove box trash bag I found under the back seat..
Replacing the front female portion of the seatbelts after driving for a year with a broke drivers belt you had to shake to get it engaged was pretty satisfying as well..

Sometimes it's those little things
If that works for you,great. Would much rather be safe,than worry about the damn stereo.I wanna go fast reliable & safe.