I rebuilt a crash box this afternoon and the gasket kit I bought didn't come with a gasket for the shifter tower. Is a gasket realy nessary or can I just use sealer. I've done the 420's without a gasket with no problems but this is the first crash box I've done. Also the dedent springs are realy weak, is there anyone who offers new ones the place I got the rebuild kit from just snickered and said good luck.