If you were unable to remove all the EMI shields, use compressed air or a blow-dryer on its cold setting to blow underneath the shields and dry out any trapped alcohol.

When all components look clean and dry, reapply any EMI shields that you removed and begin to reassemble the phone with a new battery, and a new display if necessary.

Do not completely assemble the phone yet. Make sure internal components are screwed down and everything is plugged in, including the battery and display cables, but do not apply adhesive, screw down cover plates, replace external screws, or seat the display.

It is safe to start the phone like this, but turn the phone off before you start working inside it again. You just want to test the phone while keeping the internals accessible in case there are any problems.