if you take your time anyone can do it. The examples you show are great. Done the last few of mine as well using the foam but also have used PVC and CPC plastic sheeting. Easy to use with a little heat it will take any shape you want and stay when colled. There is a plastic company across the street and I can get a 4x8 sheet for about $35
For the headliner of the '32 I used tracing paper and traced the flames off the hood