Has this been done and does it even make sense?

[jb92563]

Get a Spyder edition canopy and make/buy connectors to fasten it.

Don't mess with the engine cover, it is fine just as is. If you want to do some GT styling back there just make it cosmetic, not functional. You don't want to open the engine cover as you will loose your fire protection should the unthinkable happen.

Is the canopy going to be used while driving or just when parked?

As you know there is a LOT of turbulence while driving and if the Canopy is not well designed for driving you will be under a wildy flailing, insanely noisy canopy that will flog you hard and probably tear at the connectors in short order.

Having said that I just thought of a use for my old top assembly with the cracked vinyl window, that I was about to throw away.
I could cut it up to make a Spyder Canopy and it already has the attach hardware at the windshield end.

I'll bet you could use one as a starting point as they are only worth $150 used or are just being thrown away and the top material is typically still in very good shape.
You just need to come up with a rear attach point and reconfigure the shape and length of the last panel of the top.