Taillight lense repair kit

Has anyone used this product? I believe it is called "Plasti-fix" or something to that effect. They claim to be able to fix a cracked, or broken taillight lense up to 4 in. long. The taillight is a 1956 Chrysler taillight with a small hole in one of the raised ridges. This will be kind of hard to dublicate, so can this product be shaped and sanded after dried and then polished out? They do not have to look flawless, but very good. The plans for them are to be molded and frenched into a custom 1949 Ford, and these lights would really set it off from the crowd. I really hope for good results on this, because these are rare, hard to find taillights. Thanks guys.