Rather forlorn-looking woofer from a Technics organ with disintegrated foam surround.
Cut away the old material before prepping for surround replacement:
New surround interior-glued to the cone and wait for curing
Support the edges of the cone and verify central placement (important to ensure the coil is free from dragging in the narrow gap – hidden under the central dust cover – it would have been possible to replace this too and shim but was felt to be avoidable):
With this section carefully glued and allowed to set, the paperboard gasket was then glued in place to finish off.
Speaker refitted, sounding great and will likely last another good number of years!