The first and most important step is to get a decent set of measurements for all the fitments off the van the roof was taken off, ours were kindly provided by timber technician.
The next step was to find the centre line of the whole roof to use as a reference point for all the rest of the markings, we used dabs of masking tape on the roof which we then marked the accurate measurements on using pen. then using a 10mm drill bit we drilled all the holes for both the rear hinges and the support struts, we then fastened the rear hinges, lifted and chocked the roof, then fastened the support struts and then marked out the hole (ensuring it was going to be under the roof when down), and using a jigsaw cut it out.
Then we just needed to fasten the front roofrack which is secured in place using four bolts, took us a sunday afternoon to do all this and for us to start fastening the canvas in place and screwing the interior frame in place.
Here are a few pictures, let us know what you think? and i hope they may be of some use to some people thinking of fitting a pop top roof.
We did make a balls up and on the first attempt of fitting the support struts got the measurements wrong, so lesson learnt to triple check all measurements before drilling, we've had to bung the holes up.
Here it is before we started
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... age052.jpg[/img]
Marking the centre line and rear hinge holes
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 008252.jpg[/img]
Rear hinge holes drilled
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 008253.jpg[/img]
First rear hinge in place
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 008254.jpg[/img]
the front struts in place, although these were in the wrong place,

[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 008255.jpg[/img]
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 008256.jpg[/img]
Marking the hole
[IMG:800:600]http://img.photobucket.com/albums/v191/ ... 8261-1.jpg[/img]
After cutting the hole
[IMG:640:480]http://img.photobucket.com/albums/v191/ ... ofhole.jpg[/img]
And after all of the above
Exterior
[IMG:640:480]http://img.photobucket.com/albums/v191/ ... 56/van.jpg[/img]
Interior
[IMG:640:480]http://img.photobucket.com/albums/v191/ ... /hole2.jpg[/img]