Quote Originally Posted by nkemp View Post
You could get lucky and find a tube that fits over the existing flange to extend it (think supplement bottle, cardboard tube, or similar) . But that could take a while to find something suitable. A alternative is to cut strips of white posterboard (or cereal box ) as wide as you need to clear the dome and as long as needed to wrap around the existing flange (Circumference is 2*Pi*R or Pi*D). Then wrap and glue the strips around the existing cone. Repeat adding strips until you have sufficient buildup that it will work as a flange to hold the dome away from the dash (Probably between an 1/8 and 1/4" thick buildup).

You could guess at how many wraps are needed to get the buildup needed and cut one long strip with as many turns as needed. So if you need 4 wraps, the equation would be 8*pi*R or 25*R. The length does not need to be precise, the equation is used to get you in the ballpark.

It is a putzy process but not hard. White glue will work. You'll need something to hold the wrap to shape while drying...maybe a rubber band or two will work. Cover the dome and exiting flange with wax paper to avoid getting glue on the speaker parts and remove when done.
Or I could return them and purchase a different speaker (which is what I did). Thanks for the suggestions, though.... Very kind of you.