I ordered the RBK 9 kit and it works. My chassis was a 2016 for a 2017 coach. Below is what the Roadmaster Application Guide note says for the RBK 9 Kit use:
--For coaches with V10 engines. The RBK sku listed is for the mounting kit only. Be sure to order this AND the steering stabilizer part number RSSA.--
The other 2 kits have GVWR of 24,000 or 26,000. Our 30DS is rated at GVRW 18,000 lbs. Take a look at the coach stickers on your drivers side wall for weight and chassis date.
Hope this helps.
Mark & Connie
2020 GT5 31R5
2006 GMC Canyon (Toad)