15 minutes - 1 hour
my phone would shut down once the battery reached 4o%
it went well, I had two issues, the first was the tiny screws and the second was the accidental disconnect of a coaxial cable near the battery connector.
I used tweezers to hold and align the and it would be very helpful if the screwdriver included in the kid was magnetized.
i was insure if i reconnected the coaxial cable correctly but found out i did once i reassembled the phone and turned it on.
Myphone has been restored to its full potential and i saved money doing it myself