Of course the first thing that pop's into my mind is: why come to a BB'ing site for PL'ing help. And it sounds like you do not train with other PL'ers or have a coach. Maybe I am wrong, could be. Training with-in a small group of lifters can, in it's self, boost anyones lifts up quite a bit. If your new to GetBig than take a trip to the Pl'ing site and take advantage of the good information/help you may gain from there.
General rule of thumb is to train the squat as you train the DL, as far as (usually) 3's and sets go. Box squats are great but do require a certain learning period to do them correctly. A big squats also requires speed and quickness. Something that also takes a little time to practice and learn. Also have to define exactly where to place the bar on the back and your best feet placement for ultimate squating for your body type. I can think of a half a dozen thing you should be doing to get ready for any meet, three months or even a year from now.
In any event, try heavy support work with quarter and near half squats for a couple of sets each. You want to get adjusted to handling at least 100 to 150 lbs over regular squat weight. This can also increase the confidence factor in using heavier weight in the workouts. After these, than squat in you preferred matter for sets of 5's to set's of 3's. Try for twice a week squat workouts. Also include speed with in you rep patters. This would include those quarter and half squats. You want to burst off from the break below the knees position of the squat. Developing power will increase speed as you go along in the workouts. The only extra exercise you may need are GoodMornings and some heavy Ab work. Though you did not explain your present DL program, which may or may not include these two exercises.
This is just one workout scheme, many others out there. But time is very short for you. Best of luck.