Heres something i can never get a straight answer to- I plan to chop the roof of my 1971 Rover P6 by 2 1/2", but what do you do with the glass when chopping the roof? Is the screen cut? Someone told me that you simply sink the screen into the bulkhead, surely that cant be the case with all roof chops? And wouldnt that mean you have to angle the A pillars inwards?

The side glass should be fairly straightforward as its flat- im thinkin make a template out of MDF the same thickness as the origional glass, then have it transferred onto perspex. I have a mate with access to the stuff, but is there a certain type that should be used?
The actual roof chopping bit im fairly confident about, and its made particularly easy with my rover as the whole roof panel unbolts leaving a basic frame which can be dismantled further at the A pillars, but any tips on the subject would be welcome as this is my first attempt.