zip out rear window

I am going to modify my top for a zip out rear window so that it acts as a sun shade for me sun phobic wife.

100% all round so that it comes right out, or just 3 sides so that the bottom hangs like a flap?

Anything special about the zipper or just a heavy duty plastic NKK?

Anyone use boat window plastic?

Ideal rear window size?

3 sides will work better than trying to put in a 4 sided zippered rear...

The bigger the better.

Use heavy zippers designed for exposure to water, etc. The only convertible tops I've seen with zip out rear windows have zippers made of metal. Whatever it is, it's coated and does not seem to collect corrosion.

angela

robert its one of the first things i did on mine, when cruising on the highway at 78 with the top up and no side curtains with the window down it keeps the sun off, but most important no top buffiting, and the air goes right thru, one of the best improvements ive done on the car, any good boat shop should be able to sew one in. bill

A boat shop is what I have in mind and to use boat plastic and related zippers

Would not a zipper on all 4 sides be better?

Zippered all around would make it difficult to line up and get the zipper started without 3-4 hands. A zipper and bottom and single one around top and sides might be manageable. Post some pictures. One Speedster company used to have 3 window - 1 on either side of the large rear one like the old MGs.