Hi all,
After getting some tips on upgrading my stereo on here I thought I would add to the forum by posting my install. Couldn't find all the info I neeeded so figured I'd add to the information on this site. Hope it is of some help to others

After recently buying a 2013 FG MkII and having an amp and subwoofer in the garage from previous cars I thought I should install them.

as my car has no RCA out from the head unit I went through all the options of adding an amp or two and after speaking to (can I name shops?) I bought a Audison BitTen and some Polk Audio bd6501s.

The shop I bought these bits from have a year wait for installation and having done a few in the past i decided to do it myself.

So after buying some sound deadening and cables it was time to start the install.

Its been about three days so far (I'm a perfectionist haha) and heres what I have done:

Removed the rear panel and sound deadend the rear wall
http://imgur.com/q9HimCV


Cut 12mm MDF panels to go behind and under the rear carpeted panel to screw sub and amps to.
The rear panel was secured with metal screwed to the MDF and running up and into the slots just below the glass. Plan to replace these flimsy 0.5mm metal bits with stronger aluminium someday..... But I had this metal spare in the garage and it does the job for the moment.
The bottom was held in place by the MDF pieces that were sikaflexed to the bottom shelf.
http://imgur.com/25BSFit

6GA cable run through the firewall just near drivers side bonnet hinge mount and down wheel arch, through rubber grommet and into cabin. There was a small existing hole in the grommet that a straightened out coat hanger went through easily and then a 8GA draw wire pulled through to then pull the 6GA cable.
Was able to do this without removing the wheel or inner plastic guard but think I will have to later to silicone around where the cables go through and make sure the grommet is watertight.
http://imgur.com/ByhMZTM
http://imgur.com/YDHDrDW

All power run down drivers side and all speaker wires run down passenger side except the speaker in wird for the sound processor as it was much shorter to run behind the rear wall.

All cables for the Audison BitTen (to be mounted to MDF behind passenger seat to hidden MDF) were run down to vent holes? in carpeted rear panel and then ran hidden to various locations.

Remote to Audison BitTen was joined into cigarette lighter. This was the most difficult wire to run as it took ages to fish through from centre console back to rear wall to pull cable through. Once again the straightened out coat hanger won!

All earths connected under drivers seat.

Just finished sound deadening drivers door tonight and more work to be done tomorrow.

Not sure if these pics will show up. If not can someone tell me how to do it

Ok so after about 4 days of doing the install I'm over halfway.
Sub and box in, wiring in, sound processor in, fuse bracket fabricated, rear wall sound deadened and drivers door sound deadened.
Still have to make speaker mounts, install front speaker and sound deaden passenger door.
Heres a few pics. Wiring is still a bit messy as waiting for a new amp.
http://imgur.com/a/GsOHS
http://imgur.com/OyQOwU3
http://imgur.com/zu3vcDG