lots of people use all of those when it comes time to get lean. As far as the same receptors, no that is not exactly it, but it is a lot for the adrenals to handle, alot of stims all at once
You are cranking the thyroid, stimulating the nervous system, bronchial dilation, thinning the blood slightly, increase BP, beta cell agonism, etc. This is where the problem may lie...just too much for some to handle
Honestly it is not that bad, but some people do not even do well with clen by itself, let alone adding ephedrine as well
I would maybe try the clen w/out the ephedrine first, then experiment w/both if you know you can be ok.
the rest is really not going to be a problem simultaneously.