I am very happy I did the panel upgrade due to the list of things I found behind there (e.g., loose wires, dirt, poor grounds, extra headphone jacks, and many other things that were very concerning). Overall 53 years of history was wiped clean with this new panel.
The new panels took about two weeks to cut and ship. I also decided to send my engine monitor to the factory for a new face to make sure everything looked pretty on my new panel (added a week). Then when it came down to rebuilding I decided to have all the wiring redone (might as well) along with all new CB's. What added the most time was deciding on what to install in the panel but I kept it simple with the G5 and ADS-B transponder (the GTX 335 W/WAAS will slave to the G5 for WAAS GPS FYI).
If you have everything ready to go I am sure you could have a new panel done in a month. I kind of made decisions along the way which caused delays and added shipping time. Plus I am not too eager to fly in Texas during the 100 degree days so not a terrible loss of flight time. If you are ever in Houston area and want to check it out, please let me know. I am happy to review the entire process with anyone. I truly enjoyed the panel re-do and now I know so much about what is behind those panels (pre J).
Total 65 hours TT on the panel redo