Alleens Tacky Glue is the one to use, rather than vanilla PVA. In refoaming preparation is all, you need to use either/all of these - solvent, abrasion and scraping with a scalpel to remove every scrap of the old foam from the cone and frame. A clean and tidy area for the new surround to attach.
Glue your new surround to the cone only next (paint glue neatly and sparingly on both surfaces and press together, going round the cone), let it dry.
Some people remove the dustcap and use shims for the next bit, but...
Do a dummy run using clothespegs to hold the outer flat of your new surround to the frame. I'd put a peg every inch or so. Do it so all is equal by eye, then test you have got the voice coil central by tapping around on the cone - you can hear a different sound when the coil is hitting the side of the gap. Pressing gently on the cone in one spot near the edge can often give a good indication of where things are. Push the cone just straight in and out too. Adjust your clothespegs until its as central as you can get it, with no fouling, and no area where you feel its close to fouling. When you're happy...
Take off two or three pegs at a time and lift up the surround and paint glue on it and the frame - gently press together, replace pegs, then move on to the next three.
When you've gone all the way round, gently go round pressing down any lifted areas. With a wet brush, gently clean up and spills or untidy bits of glue on the cone - don't scrub, or you may mess up the cone - a light touch needed.
Hope this helps.
Whoops posted this before cooky, who is the expert. Do what he said!
