Insulation, Peel n seal and other budget insulation ideas

Hi there,

I'ts now getting way to hot in Idaho for me and after having a baby i don't tolerate the heat as well as i used to, i also have to keep my toddler in mind. My barracuda is my mom ride :)

Anyway, I have a bare metal roof and I have heard a lot of good things about peel and seal.

based on the research i have done there isn't much information about it being used on a roof.

Can i use peel and seal on my roof of my car, tape the seams with foil tape and then also put a layer of that foiled bubble wrap on it?

and what budget items have people used on their firewall on the inside.

I've pretty much decided i'm going to do my doors and floor with the peel and Seal, it's just the roof and firewall i'm a little lost on.

Thanks!