I am interested in the heater elements, if I dont end up putting 1st gen CL front seats in my car.

Taking the leather covers off is fairly simple... best bet is to remove the 4 bolts at the floor, all the wirring and take the seats out of the car.

There are small metal rings (called Hog rings) that secure the cover to the seat itself... once you remove the seats, you'll see them at the perimeter of the seat cover. You can either open the rings and reuse them, or just cut them off and get a bag of them from an upholstery shop, which is easier. These rings can also be found in the seating surface as well, holding the seams in the leather "in" the seat... you'll see what i'm talking about once you get to removing the covers.

Its more time consuming than difficult... you just have to have patience.