One more thing, If you make your own harness check with an electrilal supply house to see if they carry wire that is rated for very low temp. This type of wire will stay more flexible at low temp than most other types. Most of them carry or and order this wire. It may be a few more bucks but it,s worth it in the long run.
This is CABL.com posting #126231. Tiny Link: cabl.co/mGZ9