Leg muscles won't grow limiting your squats to only weight you can clean and press over your head my be limiting your progress, normally that would be a lot less weight that you can squat.
Leg muscles won't grow For squats I use a fairly narrow stance and get really really low this puts more emphasis right on the quads, although like others have and will say it works the whole body pretty much. For stiff legged deads I don't really bend at the knee at all until the last couple of reps if I feel I need to. I grab the bar at a width where my arms naturally hang at, puff out my chest and lower the bar keeping it about an inch away from my body for clearance until my back is parallel to the floor then come back up keeping everything stiff and straight. Works good for me and kills the hams, its just a big heavy exercise, I am always winded after a set (squats should get you winded too). I feel that doing those two exercises that way emphasizes the quads and hams nicely (not isolates just emphasizes, there is a difference) and I position my feet on the leg press for a more fairly even distribution. If you are using a home gym then do what you can, obviously you don't have a leg press, but my routine just has no need for curls or extensions, its getting me results and really tearing my legs up. I have used extensions and curls before, just am not using them now, I switched my whole workout up about a month ago.
Leg muscles won't grow So you only squat as much as you can overhead press? Wait a second, you just said you only squat as much as you can lift over your head, that's not "no matter how much". It's not enough weight.