Backup Light Switch Replacement

2004 Manual Trans.

I need to replace the backup light switch on the transmission.
Before I start unbolting things, is it easier to access the switch from below or through the shifter hole on the inside?

It's on the passenger side of your transmission case maybe 12" back from where it bolts to the engine, right in the center of the top and bottom. You will not need to pull the shift assembly out, just crawl under the truck.