While this video was made using a JBL horn driver, it would apply to any drivers: Altec, Klipsch, Western Electric, Eminence, EV, etc.
In it we show how to check and clean the voice coil gap, voice coil, replace the foam / felt, solder up the wires, and test the unit.
Items we used in the video:
Qpqpq Digital Microscope
https://amzn.to/3UDN6sV
Simply Speakers JBL Binding Post Pair
https://amzn.to/3QFVtTK
Rapid Remover Adhesive Remover
https://amzn.to/4aqa1xv
JBL Felt / Wool Pad
https://www.ebay.com/itm/275490127983