Yeah, I know I should have a service manual, but unfortunatly don't. So take pity on my broke ***.
I need to replace my '03 Fatboy's rear brake light switch. Once I disconnect the two wires and take out the switch, will brake fluid begin covering my garage floor, requiring refilling the cylinder and bleeding? Or is it as simple as taking the old, tore up one out and a quick swap?

Thanks for any info y'all care to shed on the repair, and enjoy the July 4th weekend.