I have 2 tanks, 2 overflow lines, and 2 small corks from Ace hardware. The corks 'live' in the cabinet with the slideout switch when they are not plugged into the overflow lines. The lines are easy to see and easy to reach with the slide IN.
Slide moved in, then put corks in; corks out then slide moves out. Having the corks and switch in the same cabinet makes it easy to remember and check.
Sherm & Terry w/rescues Steve (std Poodle) & Eydie (min Schnauzer)
2015 Jay Flight 27RLS (Camped: 102 nights 2015, 90 nights 2016)
2006 Ford F350 6.0 PSD, Lariat, 4WD, CC, LB, SRW, auto., Camper pkg.