Yes you can IF you take the top grill off. You can fit the rad in the top section and mount the fans underneath and use the top section with no problem but if you dont mind keeping the top section off then you can mount fans on top of that.
Ive just spend the last 12 hours working on overclocking my 8150 (and having dismal results) and have tried different configurations for mounting the fans and rad and mounting the rad on top with the fans underneath it and pulling air in works best. Its the coolest by 2C under full load which is a big deal if youre going for max overclocks.
I even tried the difference with the top section on and off and got a little less than a degree cooler with it off. Guess it lets the rad sit in the ambient air better.
So yeah, if you dont mind taking the top grill off, you can run push/pull. If you dont want to then you cant.