Wotcha and welcome - 22 with points hmmm sounds familiar ;) had that T shirt - great to have you onboard, we have quite a few members from Scotland and check out the vids of the highland run on the forum, one to certainly get involved with!!
Echo what others are saying in that I hope this doesnt have heavy repercussions down the line -Ireland hosts many tarmac rally stages with great success, pity it has seemed to have fizzled out over here - RIP and thoughts to the families of those involved :(
You have invested quite a bit in it so far - Im a bit stubborn and really loved my hatch so I would be looking at recovering to an alternate location and replacing the locks plus one broken window.
Given what the new owner is facing you may get £5k from someone who will break it for spares
you don't need a remap with just the filter, hold off until you get the exhaust as well. either of those filters are fine however you will find the majority of the oil free ones are consumable as the filter to catch particles is that fine it blocks up then cannot be washed hence the use of oil in the washable ones the filter is noot as fine but oil captures the smaller particles which can be washed off.
]
the 3.5mm adapter results in a socket in the cubby hole - its the same in the Impreza hatch, if you only want that then it would be no issue to get the leads and put it in yourself drilling a hole in the box to mount the socket resulting in a lot lower cost. if you want the ipod control I would go the whole hog and replace the head unit with a DAB with a functional Ipod controller - Kenwood and Pioneer both do nice units
Wotcha and welcome buddy - feel free to browse, we have a few other members owning auto sports on here - also we like to share photos and if you have any questions but cant find the answer already on here just make a new thread. You will see many threads in different sections unrelated to scooby owner-ship and you are more than welcome to get involved with those as well :)
sounds like you have an earth somewhere - remove the lighter socket and just have the connector wires in place - see if it blows again, if not it is an issue with the socket - if so you need to check the wiring - you may have chafed some insulation causing a ground during installation
Wotcha and welcome - here is some information on PCDs etc for subaru models
also hope you dont mind but will drop this in the intros section as this will give you exposure to the wider forum members ;)
http://www.carlsalter.com/subaru-wheel-fitments.html
http://www.whichwheels.co.uk/car/subaru/impreza-sti/
its the insert coloured purple on Gambits photos - as I understand it there are 2 additional options
https://www.nipponpower.com/product/1131/HKS-Super-SQV-Blow-Off-Valve-Insert.html