Carpeting Issues- non molded carpeting

[Nilsog]

My car came with a brand new carpet sealed in a box in the trunk. Today I tore the carpet out and prepared to install the new carpet. Unfortunately, it's not molded. The front part looks like it will fit fine with some trimming, but the rear section will need to be molded to the floor pans to fit right. Should I just go at it with a heat gun? Is there a preferred technique, or is it a lost cause? I'd hate to drop the money on a new carpet when I've already got one.

My other option, is to keep the old rear sections and install the front. The rear is fairly clean, but is faded. The old front section is in terrible shape though, and only got worse when I tore it out- a previous owner had put 4 screws in to hold the carpeting down around the heel rest. Those were a joy to remove.

Thanks for the input!

 

[ssba]

Heating the back side with the heat gun will work. Heat up a area and press into place and hold
till cool enough for it to take a set. This may take awhile due to having to work a small area at a
time.
I use a drapery steamer and work from the top side. Much easier and can form a larger area. This gets very hot so I use the rounded off end of a two by four to press/ hold carpet into the
contours of the floor pan till cool enough to be moulded into shape.

 

[Nilsog]

Thank you. I realized I'm a total moron though, I put the rear carpet in backwards and couldn't tell the molded sections from the wrinkles. Once the carpet flattened out a bit I realized it had the molded areas. It will still need some heat gun work I think, it's been rolled up in the box for at least the last 8+ years. Hopefully they turn out alright.

 

[Matts440]

I always put mine out in the sun for a bit before I install my carpet works just as good as a heat gun