Rifleman, unless you have a half bath in the garage (and I don't think there is), you have one black tank and two grey tanks. Yes, the spec's call for one grey at 84 gallons or so, but it is actually two; one in the bathroom and one in the kitchen area. Your electronics area is set up in case there happens to have the half bath. Welcome to the forum, by the way!
Jim in Memphis, Wife of 51 years is Brenda
2019 F450 6.7 Powerstroke
2018 Mobile Suites 40RSSA
2021 40' Jayco Eagle
2001 Road king w/matching Harley sidecar
2021 Yamaha X2 Wolverine 1000