Re: A few questions from a noobie
I've got a DA2, and always was interested in Zomwit's beast, good to see it's back in the club :)
As for the idle, clean out the ISC solenoid, which I might do a tutorial on soon. Very easily done. I had similar problems and cleaning it out fixed it.
As for the stereo, I was hesitant of changing it too because of the rear controls, but in the end no one used the rear controls, and neither did I, so it was pointless and I forgot about them. Not only that, but you've got no CD, and the stock head unit by today's standards is a bit of a heap of shit. I put in a double din Kenwood HU with CD, tape and radio, and I don't regret it for one second. It's got a good beefy remote, and sounds infinitely better. Trust me, get a new head unit.
As for wheels, 18 and 19s are far too big, and will look gay. I think even 17s are pushing it, because LTDs look best long and low, and anything above 17s dwarf the car too much, ruining its long stance. Even 16s are the best I think, so it looks really long but the rims aren't too small.