I grafted in the section in from the 75 Cordoba's original roof around the opening. I have done a lot of customizing so to me it wasn't hard to do but I have been doing restorations and custom work for years. It takes a lot of time to graft in a moon roof correctly. Then once the moon roof opening section is welded in and the cassette box is installed into position, drains have to be run and then I had to figure out what to put up so that I could attach head liner material too and you wouldn't believe what I used... I used a Bath tub/shower surround...