full aluminum tubs?

I made poster board copies of the tubs and taped them in place. measured carefully from the backing to the fender every inch and transfered that to the posterboard. Cut it out and then used tape and pieces of posterboard to fill in the short areas and cut the areas that were too long creating a tight fit to the quarter panel. Then transfer that to the wheel tub and cut. Seal it with silicone sealer or I've also seen fiberglass used. Either way fit the posterboard first before you cut the tubs.