I'm wondering how important the rear window is in an MK1 as far as structural integrity and rigidity goes? The reason I ask is because i'm thinking about making mine with the ability to roll down (i think the del sol has the feature?). I understand the issue of heat from the engine and that it would mess with aerodynamics while down but i'm not planning on removing it outright, just having it be able to roll down for a roadster feel.