Curtains for Cal 2-29

[Bordier]

We just bought a 1978 Cal 2-29. I would like to fix up the cabin. The cabin has a vinyl headlner, wall covering, and seat covers that is probably original. Although it is in good shape it is ugly and I don't find vinyl seats comfortable. I would like to cover the seats, and install curtains. I am not sure how to mount the curtain drapes. I found a good site that has a drape system (Beacon Fabric) but I am unsure about mounting the plastic track to the cabin wall. The headliner is in the way. There is about 1/4 - 1/2 inch of air space between the fiberglass wall and the vinyl headliner. Any ideas? Also, can I just cover the cabin cushions with home decor upholstery fabric and spray them with scotch gaurd to make them water repellent or is Sunbrella Fabric reccomended?