I recommend that you work out how you will deal with the electronics work first, and if you are not adept at rooting / hacking linux systems, you outsource that part of the work to one someone that is adept at it. While I am comfortable at linux, Tesla has made it very and increasingly hard to get root access of your own car. For that reason, when I bought a salvage car I opted to pay someone for that work.
Parts for the age of car you are talking about are readily available through eBay, craigslist, and dismantlers. If you are adept at rebuilds, most of that work should not discourage you as Teslas are essentially "legos for big boys" and are pretty straight forward.