Its okay if that day or two rest turns into a month or two. Or even a year or two. It is a hobby that you can work on when you want, not a job you have to go to every day.
Throw away all the receipts for things like nuts, bolts, paint supplies, trim items, etc. If you sell the car it will be obvious that you've dealt with those but showing receipts for a professional engine rebuild, etc. could be very useful. The reason you don't want to keep receipts? You really don't want to know how much money you are wasting on that d*mned vehicle.
Also if its a Plymouth up through 1948 please let me know what you find for cross references so I can add it to my database at http://www.ply33.com/Parts/numeric That database got started just as John-T-53 suggests you do: As a list of parts cross references I started when I first started working on my car.