Wow those are impressive squat and deadlift totals, time to focus a little more on the upper body. How many sets of each are you doing? Or do you mean 1 set of 5 reps ()?
I wanted to improve my upper body strength so I do bicep curls to start every workout, whether it's a chest or leg day.
Also, about pre-workouts, I've found that eating some dark chocolate seems to give me the same boost as the pre-workout samples I used.