Lets Match drill the 705L Shim using the 705F channel as a drill guide. SImply draw a center line on the shim, view the line through the channel, clamp and drill to #40.
I have left the 3 parts that make up the seat back adjustment (705J, 705K and 705L) about 1/8" long and will later trim them to the exact same length, 16 1/4", after they are drilled. I thick I'll get better end alaignment of these 3 parts if I wait until thet are drilled. You'll see in a later post if it payed off.
Make sure you mark these 705L shims not just left and right but also inboard and outboard. Sure don't want to get them mixed up.