How do you get these out? What is the secret? We couldn't get ours out today and did not want to just yank til they came out!

Then, after the seat parts are out, what about the panels next to the rear seat, under the quarter window?

By the way, this is for a '66 F85 2 door.

 

I don't have a '66 but most GM cars I have had were the same. The bottom cushion is removed by pushing it back, lifting up, and then pulling forward. The back cushion is usually removed by lifting it up after it is unfastened, the bottom of the upper cushion on mine has two places where it is bolted down on the back of the seat frame, seen ones with metal hooks too, obvious when the bottom cushion is removed. I don't know about the side trim on yours, the common way is for them to hook over the edge of the metal by the window and screws or push type blind trim fasteners holding them on the edge by the door. The chassis or service manuals should explain it all somewhere too, look for build sheets in those cushion frames.

Allan

 

I'm going to add to what Allan said. Move the front seat as far forward as possible. Then get in the space between the d/s front and d/s back seat. Then use both hands and push the front of the bottom seat backwards. This may take some effort. You should feel and see it move backwards. Then do the same thing on the p/s side. Then lift the front of the bottom back seat straight up and pull it forward. It should come right out. Once the bottom seat is out, you'll be able to remove the top of the back seat easily.

 

And just to add to what's already been written, the seat bottom is retained at the front by two stamped sheetmetal "J" hooks that catch one of the bottom metal rods of the seat frame. There's often a small barb at the end of the short leg of the "J" that can catch the rod if you're applying any upward force. I've found that you actually need to push down and rearward on the front edge of the seat cushion. If you pull up on the cushion beforehand, you can usually see these hooks by looking in the space between the seat cushion and the floor.

 

The seat bottom is retained by two brackets in the floor pan, Pushing backward the seat bottom at floor level will flex it out of the brackets and you can then lift the front of the seat and slide it out. In 66, the top part hangs on two hooks near the top and two steel straps welded to the floor pan are folded over corresponding frame pieces of the seat to hold it at the bottom. After removing the seat bottom, bend these straps so you can pull the lower part of the seat back forward, then lift to get it off the two hooks.