remap question
 

thinking about getting my95 wrx remaped but this is my first subaru so i was wandering what exactly is involved in remaping as i stay away up in stornoway in the western isles the closest place i can go is edinburgh for a map its got a full stainless from the turbo and it hasnt been mapped since the exhaust was put on so i was wandering what would the remap actually involve as its a long way to travel so any kind of help would be great??

basicly the mapper needs the car for a few hours to do his/her thing