It actually sounds like a perfectly practical remedy to your ceiling problem - but if you want to build that base for the press - esp when using heavy weight, you might want to do this instead:
Rather than using a box to perform a stunted version of the whole exercise, split it up.
For the presses, take a seated position, ideally in the rack using the guards (like in a Savickas press, but from just above the knee) and clean (or is it jerk?) to the shoulders, then into the press. Use the lack of lower body momentum to build form and core strength.
For the power cleans, perform the conventional way: clean to the shoulders and repeat.
When and how you incorporate these movements is at your discretion of course, but I reckon doing it this way may be a good idea.
W.A. AMATEUR STRONGMAN
Axle clean-press: 100 kgs (220 lbs)
Bench press: 135 kgs (298 lbs) - 1st PL meet 16th October 2011
Deadlift w/Barbell: 180 kgs (397 lbs)
Deadlift w/Hexbar: 225 kgs (496 lbs)
Farmers walk: 240 kgs (530 lbs), 50 feet
Front squat: 100 kgs (220 lbs)
Log clean-press: 100 kgs (220 lbs)
Strict OHP: 85 kgs (187 lbs) 3 reps
Tyre flip: 260 kgs (573 lbs), 100 feet
Last edited by Abaddon; 09-01-2011 at 02:14 PM.