Apogee Duetta Signature: Optimum placement


I am setting up the Duetta Sigs in a room 16' x 15' with an 8' ceiling. I have them on the 15' wall 20" from the side walls and 36" from the rear. The distance between the left & right m/t ribbon sections are 7'. The tip back is 2.5" or 2.5 degrees. The toe in is 1/2". Listening position is 9'. What changes do I need to make to this basic configuration to acheive the best sound? I am using an ASR amp which provides 290 watts at @ 4 ohms & 520 @ 2 ohms. The speakers have a single run of speaker wire and jumpered on the back terminals. I have, but not installed the crossover upgrade kit (came with the speakers) for the caps, resistors & inductors. How much difference does the upgrade make? Is it worth the hassel of taking apart the speakers to install it??
128x128darrell
Thank you all for your excellent help!!! One more question please.

Which would be the best audible improvement: Installing the crossover upgrade OR purchasing an Apogee external DAX ????

Once again, Thanks for your advice!!!!!!!!!
The best thing you can do is BI-WIRE these speakers. Of everything I tried with these it made the buggest difference in sound....