Yeates689,
You don't say where you live in CA and while I don't know how every town, city and county works, I do know about some of them. Most sanitation dept's don't really give a crud if you use your cleanout to dump your tanks. I didn't have an easily accessable cleanout in my homes sewer system so I installed one. It just so happens that it is where I can access it with twenty feet of one inch Sewer Solution discharge hose. The cleanout I installed is a 1.5" abs pipe with a coupling on the outside of the house. I used a sewer test plug to cap it off. Not a good idea, it would be better to use a slip - FPR coupling. The slip - slip coupling I used has deformed from the probably excessive pressure from the test plug. I try not to dump when there are any City employees around, which is very seldom on our street. Actually I don't give a rats a$$ if they see me. The cleanout is properly installed and meets code.
If I were you, I would just install the clean out and use it when needed. But I have been known to mentioned the fact that I worked for the City for 33 years and sweet talk employees out of stuff.
I use a Sewer Solution instead of a 3" slinky or a macerator pump. I have to pump over a planter that is about 18" high and it works pretty good. The original manufacturer sold to someone, maybe Camco, I,m not sure and of course the price is three times what I paid and the customer service supposedly sucks. My waterhose quick disconnect broke and the only place I could find a replacement was the manufacturer. A tad Spendy. Oh yeah, the SS has several adapters to fit different sizes of common sanitary waste pipes, mine is 1.5" but it goes up to 4.0 inches. This gives you an air tight coupling of your drain line and the sewer line.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
BrakeBuddy Classic II