Leak Occurs After Installing New Primary Drain Pan

Recently had a new primary drain pan installed in York central air unit to eliminate water leaking. Condensing unit is located in the attic. Outside unit was replaced in the Fall.
The leak continued, the heating company returned to tip the unit slightly towards the drain.
Most of the leak has stopped, but now leaks on the side closest to drain. Any thoughts on why it would still be leaking?
Sure, it's an old one....place was built in 1987 and is original equipment.
Model #M+HD024SA
Serial #EHUS388071
Heating company has suggested installing another pan beneath this one and piping it to the drain. Good idea?