Modern Vespa

I've decided to put a new seat cover on my BV. Had taken the bolster off for more legroom, but left with holes, which I thought I'd covered nicely with plastic plugs...but over the years has stretched and torn the fabric a bit..... soo, starting over.

Just curious if anyone has added any materials under the cover successfully. It seemed an interesting thought (I expect the foam has lost a bit of padding, and being tall any extra height isn't a problem). But it could turn out to be a hot mess as well. I know, replacing the foam might be an option, but I'm diving deeper than I'd wanted to go anyway.

I've had experience working with vinyl in the past and my mother is a pretty good amateur upholsterer so I have a team ready....

I am interested in adding a bit of foam to my seat too but also a bit nervous about messing it up. I have worked with a few different foams and wanted to say, in case you weren't aware, that a bread knife with the scalloped edge is a great tool for cutting foam.

Thanks...I think I knew that once, but good reminder!