Efficient way to replace footage.

[Outpost24]

What is the key to replacing footage so that the .png is in the same position as before (more or less).

For example: replacing pants on a character with a newer version. 

[Mylenium]

Pre-compose whatever parts need to be substituted and replace the contents of the pre-comp.

Mylenium

[Outpost24]

Thx.

If I duplicate the Pre-comp and then replace the contents in the window to the left, both Pre-comps are updated. Not seeing answer yet.

[Outpost24]

Ok got it thx

[ShiveringCactus]

If you hold down the ALT key and drag your replacement PNG file from the project panel onto the original layer in the timeline, it will replace it.