will1018

Hey guys I have a few questions regarding audio work. I've looked all over the site and found answers to most of my questions but could not find the answers to a few. Sorry if these have already been answered elsewhere.

In my TL I redid my entire sound system. I replaced the stock speakers and speaker wiring and put in 2 aftermarket amps. However, I did not integrate my system with the stock HU so the HU is essentially useless. Right now my system only receives audio from the AUX-in of my equalizer. so if I want to adjust volume or anything else pertaining to the audio, I have to do it through whatever device is playing the music. I was fine with this at first but its becoming a pain. I noticed a few people are installing tablets into their cars and it sparked my interest. I want to install a tablet as well as remove the stock HU and replace it With a double din aftermarket one. this brings me to my questions.

1) i have heard that some higher end car's head units are part of the car computer and if removed will cause the heating/AC and various other dash electronics to stop working. if i remove the stock HU will everything else in the dash still work properly?

2)Since i re-did all the speaker wiring and such, could i get away with hooking the aftermarket head unit up to the power, ground, remote and antenna of the stock HU and use pre-amps to connect the new HU to my amps?

3)does anyone know if a regular double din HU will fit in the place of the old HU? (I know that the knobs of the stock HU go into the metal side pieces. I was going to take care of that with some low temp plastic, as Neibur3 did in his install)

4)a little off topic but I was also planning on installing an infinite baffle and I was wondering if anyone had the dimensions for cutting the MDF that goes against the cabin wall of the trunk.

Thanks