Welcome to the club Stuart, your deffo in the right place for what you want!
If the Challenger is the car you want then go for it..........but be aware that you have chosen probably one of the most expensive on the market to attain!
As for liking other Mopar cars these are like drugs, never liked the 71+ B bodies or the pre 67 A's.........I would now chew my arm of too own one or any of them.
The longer your around and the more shows you go to, the more the varying shapes and styling ques get to you, so whilst the Challenger is a greeat car with good resale, there are many out there that can tick all the right boxes!
Trying to be sensible (and knowing nothing about disability mods), i'm not sure what exactly is entailed in modifying a car to suit. Nobody.......Or very few buy a car for investment, so if resale is not an issue the thats okay.
But if it is, cutting, modifying and adding to the car something that cannot be reversed back, may well affect future sale value and ability to sell (many who have £20k will want unmessed with cars)!
Another thing worth noting is Mopars are the most expensive of the big 3. The majority of Mopar parts carry a premium (10-30%) over what someone with a Ford or Chevy will pay, so be prepared to pay that little extra for a true muscle car

!
All that said, if you still have the itch that has to be scratched, they are some of the best cars out there!
You will also become part of one of the best American car clubs in the UK, who's members are amongst the most friendliest and knowledgable out there. They also play a big part in the No.1 event in the UK (Mopar Nats)!
Just be prepared to lie to the wife a bit more.......Lifting the hood will cost £100 in shipping alone............
