I did a search for this but was coming up empty, but if I decide to have my oil changed locally (Acura dealership about an hour away), how do I change the computer to reflect "Oil Life 100%?"

I'll have to look but I think the dealership did offer me two free oil changes after purchasing my 2006 TL and it even seems like they were going to give me a bottle of touch-up-paint which I already unfortunately need for a spot on my passenger door.

Oh yeah, I normally change my oil at 5,000 miles...so it is easiest to remember, but my oil life gauge shows that I have 40% life left. Which should I follow?

 

It's all in your owners manual. I don't know the procedure by memory, but I know it's in the owners manual. I suggest you look there.

 

The 3G Garage has a wealth of information:

F-034: Oil Life reset
https://acurazine.com/forums/ramblings-12/when-you-mods-close-advertising-threads-91245/
https://acurazine.com/forums/audio-video-electronics-navigation-22/subwoofer-help-90084/

F-157: Does resetting the MID in the middle of the Oil Cycle reset other services?
https://acurazine.com/forums/showthread.php?t=119780

C-028: Oil change!? by MID or miles
https://acurazine.com/forums/show...549&postcount=7
https://acurazine.com/forums/show...383&postcount=5
https://acurazine.com/forums/show...32&postcount=10

 

^^this. cliff's notes version: FOLLOW your MID. and flip through your owner's manual....that too has a wealth of info you seek regarding the care of your car.