I suggest keeping and installing the spoiler....but only to use as a mounting point if you do decide to go with a kammback. Otherwise, I'm still trying to figure out possible mounting solutions without the need to drill into the trunk.
Also, in addition to driver/driving mods, proven aero mods i've done to my del sol that will not effect functionality.
1. Rear wheel skirts
2. Underbelly tray
3. Front wheel covers
4. Side mirror delete - obviously will greatly effect functionality, but the mod does give a big improvement with aero.
Kammbacks on a del sol are promising. Here are some of my previous attempts in the past:
http://ecomodder.com/forum/showthrea...ckup-7587.html
**The dead zone between the roof and the cardboard poses an aero problem, so a kammback will definitely need a smooth transition between roof - kammback.