Since it's a hard top with no center pillar I've assumed that the pillar at the rear passenger's ear was called a B pillar.
These are the 5x7 "ultra thin" speakers that I installed. Sound quality is "just OK".
https://www.retromanufacturing.com/p...nt=31320903246
As you can see in the photo they do protrude through the liner a little bit. THere is an internal steel framework that these are fastened to- no cutting. I spent about an hour shimming with various thicknesses of hard rubber washers to keep about 1/8" space between the back of the speaker and the exterior sheet metal of the car. It's not a perfect install but works for me.