Sony HU with Connetcs2 adaptor will operate the HUD and the stalk conrol. Most other units have stalk but not display.
Speaker wise the rear pods and the door pods are 5.25inch so get some good 5.25 co-ax speakers for the rear and get components for the front that have a 5.25 woofer.
You can remove the top of the dash and replace the tweeters in the original mountings if you get a custom fit adaptor with em or just do what I did and fit 1 inch tweeters to the interior door mirror trim.
Fit the crossovers in the doors or under the dash.
I have Focal 5.25" woofers, focal x-overs and Pioneer tweeters at the fore, Infinity 5.25" co-ax in the rear, a Kenwood 10" sub with an Alpine V-power 300W amp. The HU is a Kenwood 8027.
If you go Sony to get the Display to work then I am selling a DRNS-003 adaptor which will give you ID3 and CD-Text on the HUD along with RDS Radio name etc for the tuner.
Si