My guess is that you will be working with older American cars, which is typically easier overall when it comes to laws.
It should be mentioned that when a car has reached the age of 30 the yearly inspection is changed to every two years instead and you no longer have to pay roadtax (vägskatt) for that car.
Laws recently changed from inspection every year, to inspection within the next 14 months, counting from the last inspection, (cars younger than 30 years)
Worth noting is that a car aged 50 and older can have a final inspection performed and never have to be inspected again, this is how we get away with leaking old cars a lot easier xP With that said you can still get pulled over and be forced to do a new inspection if the police consider the car to not be roadworthy.
Ls-swaps is difficult if you want to make the car legal, there are a ton of laws that I wont go through in this post. The best way is to swap a car that is 50 years and older that have had its final inspection, although not legal it's not considered a crime and the police can let you go in a lot of cases if you just behave.
Converting a naturally aspirated engine to forced induction is not really possible without some laws stopping you. There are some loopholes tho.
Converting from auto to manual and vice versa is really hard to do legally on cars registered 1993 and onwards, although possible, it's not really feasible.
Im not entirely sure how you view the average Swedes ability to speak English. My personal experience from the average owner of an American car (owners age ranging from 40 and up) is usually really bad, pronunciation being the biggest problem, just someting to keep in mind. I'm comparing this to my generation (born in the 90's), so older people might perceive this differently. I have had two American friends visit a few years ago and they have both confirmed this.
If you have more questions feel free to ask
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