Back when I started my cleansing journey more than 10 years ago I also went through all the different protocols including prolly 18 20 Liver Flushes over a 2 year period. If you refer to colon cleansing as in enemas and colonics then that is just not for me either but I have done a few rounds of oxygen based protocols like Oxypowder which is pretty easy and non obstructive so you might wanna czech into it. I saw a video recently and I can't remember where and this guy chronicled in detail including weighing everything that went in and everything that came out! in his juice feast and he talked about passing rubber like stuff in the latter part of his feast which I assume could be refered to as "plaque".
There's not much to sell when it comes to juice "feasting" like there is not much to sell when it comes to Liver Flushes or The Master Cleanse etc. An industry grows up around those things to serve the "needy" lazy people who won't take responsibility for themselves and do their own research. Google "juice feasting" and you'll find a number of personal blogs of folks daily accounts and testimonials. There are also some videos on YouTube