Dude.... 3/8" its a big gap between the surround and the basket //content.invisioncic.com/y282845/emoticons/crap.gif.7f4dd41e3e9b23fbd170a1ee6f65cecc.gif
If the parts are already glued (spiders/spacers/coil/cone) there's nothing that you can do because the only way to make the recone fit, will be if you remove and remplace the spider/spacer of the bottom BUT if you do that, you will give the coil a different aligment on the Top Plate thats assuming it's already set in the midle, Otherwise you need to set it up first and then deal with the other parts. AND The other way to do it is using another cone style which I would do if you haven't glued the cone yet...