I've spent 23 in handling auto insurance claims. We used to use the Mitchell Manuals, but of course everything is computerized now. The manuals paint times were primarily for refinishing new replacement panels or panels not so badly damaged that they were repairable. I don't recall that the manuals had any times for complete repaints. How could they, since vehicles came in all different sizes, with/without vinyl tops, etc. You also had to consider R&R time depending on what trim had to be taken off, etc.

In the end, it was always a matter of what was the best deal you could negotiate with the shop - and it still is today. Many factors went into the shop's calculation such as the color (on reds, yellows, etc. the paint materials actually cost more than on say blue or white) how slow or busy the shop was, and dozens of other factors.

You also have to consider that Mitchell times were to (supposedly) reproduce a factory equivalent finish. On Mopars from the years you own, that would mean waves, orange peel, drips and sags. It was NOT the time needed to produce a show quality finish. I can tell you that the main reason most shops do not want to do restoration work is because of the time to block sand the entire body. This can run to hundreds of hours and most body men at a production body shop will flat out refuse to do it. It is grueling labor and they can't "beat" the book time like they might hanging a quarter panel or skinning a door, so the body man typically is losing money doing it unless he is getting a higher rate than he would for normal body work.

Also, any wise shop will want to strip off the old paint before they refinish as there is always a chance of incompatibility between the old and knew paint that could cause lifting, shrinking and such.