Run the cpu case with the side off and the radiator front.. (next to the metal front wall) facing into the open air. If this reduces your temperatures much if any, then that front case wall has be be CUT OUT in front of the rad. With everything as-is, the radiator really should be the most limiting factor using that setup.
Personally, I put my heatercore sandwiched in between a push/pull config. But, the fans do no good if they dont have 80% without restriction (my exp.) You can make the fans much more efficient if you use a shroud though. Make the
shrouds yourself. The cost is minimal, you can do it in a day and it will be custom to your heatercore and fans.
The favorite part of my case was making the inside and outside components out of fiberglass, and it performs like a champ.