Doing vectors may be more work than you need to do depending on how flexible you need your PF elements when aligning a hardtop. If you're just doing stitching and image cleanup you might consider doing color masks in Photoshop and stacking them in the order they would have been screen printed. This would preserve the fine detail of the linework better than beziers. I often see plastic repros that have been auto vectored and they are all missing substantial detail.

Attached is a quick sample (45 minutes) of building screen printed layers in PS. Needs a little touchup yet but you get the idea.

001_sample (resized).png