Your infestation is bad enough to break out the pesticide. If you can, capture the big mop bugs and move to a safe area. Spray the affected plants with a pyrethrin based product. Apply in the evening and repeat every 2 days until you aren't seeing any new bad bugs. Make sure you spray the bottom of the leaves, aphids like to hang out there. The aphids will die in place and leave a tiny carcass. You can gently wash the leaves with water and your fingers to remove the dead bugs and some of the honeydew they excreted.
OK so how do I kill em?
No problem I only know what these guys are because I found them in my garden a few years ago and looked them up in the Texas Bug Book, which had a pic that was pretty much identical. They are pretty cool little guys, sometimes they raise up the front half of their bodies and wave it around like some kind of aphid hunting dinosaur claiming it's territory.
Awesome. Thanks for correcting me guys.