[modelman]

Jim-I have many years experience working with fiberglass molds, male and female molds and parts and I have also done some vacuum parts from plastic so I think they are both easy to do. Depending on how much detail you want in the lids would be the determining factor for me. If you can make a model of what you need then you can make a mold from that and a couple of layers of glass cloth with epoxy resin would make a strong lite-weight almost clear lid. Plastic probably would be quicker since it takes less prep work on the molds for plastic and you can pull it down with a standard vacuum cleaner. But, you don't need to do this in your house so finding an oven large enough may be a challenge. I used a small toaster oven for small parts. Ask questions if you want too. I will help if possible.