Clever rewiring idea. Could be used as a band-aid to allow the airplane to permanently fly sans MCAS.
Not sure using a revenue airplane for flight testing might be authorized, though. Better leave Boeing do the rewiring and first test flights and foot the bill ;-)
pretty sure there is only one test aircraft, BOE1. It likely has quite o bit of testing hardware installed.
Once the 'fix" has been installed, there will be flight testing of each revenue aircraft, especially by the Airline Chief...details unknown at this time.
Whether or not test data on, e.g., stability can be withheld from the public as proprietary is not a settled question. I very much doubt that, in the long run, the answer will be that it can.
I am sure it will be withheld, just like FOQA/FDM/FDA data...