Is VERY easy and inexpensive to do..
I just clean both surfaces the old surround attached to as well as possible, and use a aa battery to center the cone, and glue the new one in.
you can get fancy with shims and test tones but i have done it dozens of times with a aaa or aa battery with a wire lead attached to both +/-
One polarity will draw the cone in, the other will push it out.
this link should explain it better than i
http://www.audiokarma.org/forums/showthread.php?t=384476
