Dumping the FBO timing advance plate.

Which one, or all in?
I ran 22 initial and grand total was 52 with vac advance for years and was getting 25mpg on the hiway.
I don’t pay much attention to fuel economy normally, but I stopped for gas on a trip at 250 miles and it took 10 gallons to fill it back up.
That’s the only reason I know.

Apparently Magnums like a lot of timing, unlike my LA.
Plugs look great as well, and been in there for 5 years.
The 48 total. I assume that's just initial plus mechanical with no vacuum assist, right? If it likes it and doesn't spark knock, put the fire to it.