Deformed Helmet - HELP

I have the white vinyl Don Post helmet and have it painted and the T-Visor area cut out and made the proper shaped T-Visor for it. But because I moved I put it all in a box and a year later my helmet is deformed! HELP!

The face is totally wonky and I tried supergluing the visor in but it looks horrible. I Had to remove it and clean it all up. Ive seen some people use a metal rod to keep the mask in shape but what do you use to adhere the rod to the inside of the mask? Ive sanded the inside to give it grip but no way in hell will hot glue work on a hot day. Suggestions please and if you can post photos of how you did yours that would help. I am guessing I will have to dremmel the thickness of the T-Visor area of the mask down so I have a flat surface for the visor to attach to.

First off youl need to reshape the helmet, id sugest using a hair dryer and heating it aound the sides of the helmet and the back and reshaping it , you can also do it in a tub of hot water , and look in to getting a new visor , probly a green face shield and cut it to the same shape as in my pic, this way it will hold position beter Dont need to worrie about the holes, if you plan to glue it, but if you want to screw the visor in, you glue an attachment method in like chicargo screws , or T nuts this way you dont mess up the visor,,

Ok helmet is back in shape. Now to attach the visor.

Thanks