Got my e90 335 about a month and a half ago and already got mod fever.
Saw this thread the other day for the spec dock and anted one, but being the cheap and creative mofo I am, I decided to make one for MUCH MUCH less..My next project is going to be a custom sub enclosure out of fiberglass to fit in the drivers very rear.
I started off by buying the same kit as the specdock for wiring (they use the is76 which has RCA + video) and I used the is75 which is exactly the same but just has rd/white for audio.
Isimple IS75 kit for $2 + $5 shipping:
Got the kits (gonna make one for my roommate with an e92) in 3 days.
Picked up some plastic bond (will stick to plastic,metal,etc ) for $9 at Lowes, as well as some Plastic Epoxy $5 who's brand escapes me. I will look when im home. I made this kit overall for under $40. Im not done yet though. Just need to fill in a few small holes and then coat with either flat black paint or maybe some plastidip.
Considering the ashtray is only $6 from bmw parts this is easy to reverse or just have an extra of the ash tray.
I started by sanding down for grip then filling the ash tray half full with bondo I mixed and let it harden. I then filled up the rest to the top and put some saran wrap over the top and stuck in my igriffin ipod ock adapter piece and then smoothed out the sides. Once the bondo dried the igriffin adapter popped out and left in place, and nice mold that holds it in.
Next I marked with a marker the angle that the ipod sat in the tray as well as the position where the dock connector port went. I then took a drill and drilled out a rectangle slightly larger than the connector port. I took the plastic surround off the connector as well as the 2 metal prongs that stick out to hole the cable into the ipod. I didnt take pics for the whole process as I forgot but you can easily see.
Next I took the epoxy I bought and mixed it and put saran wrap again under the dock adapter and fed the cable thru and into my ipod. You arent going to get epoxy quite as far down at this point so dont worry about your ipod gettin epoxy on it. Once that dried I took out the dock adapter and put more epoxy all around the port (CAREFULLY) and then let that dry. Next I sanded it all down smooth and checked for clearnace on the ash tray top.
I wired the dock in and gave it a try and it works perfectly. I just need to do the final bondo and painting. Much cheaper (and only took a combined 2 hours or so to make)