Acidfast7, That might require a derailleur hanger extender, super long b screw or MTB long cage derailleur.

I recently faced the challenge of getting easier gears on our tandem (see tandem forum for thread). Started out with the same idea of using a wide range cassette. Guys pointed me to the fact that many front derailleurs can handle a very wide range of chainring sizes reasonably well.
We changed from a 30/39/52 to a 24/39/52 and that gave us seriously low gears (MTB on low end, road bike on high end). The 24-39 transition isn't beautiful and it needs a chain catcher, but most definitely works and has been a life saver on the mountains of our most recent fully loaded tour.

We did change the cassette from 11-32 to 11-36, but that difference is basically negligible. Front chainring swap was by far the cheapest way to go. Didn't even require to lengthen the chain.