Drain Height for New Sink

I am in the process of remodeling my kitchen. I purchased a new undermount sink, and during the installation of my base cabinets noticed that the drain line does not appear to be low enough for the sink I purchased. The sink is 12" deep and I also want to have a garbage disposal. If I'm not mistaken, the drain location should be approx. 10" below the bottom of the sink to allow for the garbage disposal.

I have opened up the wall and noticed that the sewer riser runs vertically into the garage space below. There is a clean out located directly below the cast iron T to the drain. I was wondering if this clean out can be switched with the T so that the drain is now lower. If so, what is the proper procedure for removed the fittings. I know how to loosen the straps, but how do I remove the rubber collar?

Thanks for any advice/help you can provide...

I would select your garbage disposal and check out the installation guide. Some are different, so see what height it specifies, but 10" sounds right. It sounds like you have hubless cast iron if you are talking about straps and sleeves. If this is the case, you are in luck. It is pretty easy to move things around. If the placement of the cleanout is at the right hieght for your trap, you are indeed fortunate. Just loosen all the bands, slide the bands off the sleeves onto the fitting and roll the sleeve onto itself back far enough to remove the trap and cleanout. Leave the sleeves rolled back on themselves. Reassemble the fittings in reverse order. Reinsert the two fittings in the reverse order rolling the sleeves back in place. You can lubricate the fittings with dish detergent if you have a hard time with the sleeves. If you do not have hubless cast iron fittings, then ignore the above.