I've had a system in all 3 of my SHOs, along with helping all my friends with theirs. My current SHO is the first I've had kickpanel speakers in, and I'd never go back to door mounted. The way I did my kicks isn't very optimal, but I still want a functioning parking brake, so I had to work around that. The Taurus doors have horrible speaker locations since the speaker is so high up in the door, but it doesn't sound as bad as it could.
I'd recommend kickpanels in a Gen1/2 to anyone, speakers made for on axis listening would be even more optimal, but off axis works great also.
NJSHO, I remember seeing someone on carsound.com with speakers in the door panel, but it was a regular Taurus, so its going to be hard to find again. Its best to mount the speaker to the metal skin of the door, but mounting on the doorpanel itself, with some reinforcing should work too. Thats assuming the motor isn't in the way, and you keep it far forward.