I remembered there being a problem with my old C yokes spreading open when I tried to squeeze a 1/8" rivet. Brian Decker said he never had a problem. So I completed a test squeezing 1/8" rivets with all my yokes. In each case I used a 0.25" AN426AD4-4 long flush rivet and adjusted the pneumatic rivet squeezer to have an air gap of either 0.145" or 0.090" when the squeezer was closed with no part/rivet in the "C". The rivets all squeezed down. The gap and final length results by yoke were:
gap squeezed length yoke
0.145" 0.193 3.75" heavy duty (new)
0.145" 0.190 3.0" standard 2 die type
0.090" 0.153 3.0" standard 2 die type
0.145" 0.190 2.5" close fit 1 die type
0.090" 0.149 2.5" close fit 1 die type
0.145" 0.170 1.5" standard 2 die type
0.090" 0.125 1.5" standard 2 die type
0.145" 0.190 3.00" longeron 2 die type
0.090" 0.144 3.00" longeron 2 die type
So there was only a slight change when going to the longer reach yokes. And no difference between my old 3 inch and the new heavy duty one that worked so well yesterday. Maybe I need to change the test to squeeze a rivet in a piece of metal similar to a real situation. Or maybe I didn't have the squeezer gap set right in the old days. I'm not going to worry about it for now. I needed the longer reach yoke anyway to be able to squeeze rivets in more situations.

Riveted final 3/32" rivet close to the firewall recess using the new, heavy, squeezer yoke as the backplate. Tried to rivet one of the 1/8" rivets close the firewall recess the same way and decided to use the 3x rivet gun later after the nearby pro seal cures.

Worked with the rudder bar mounting blocks and center support.
-Checked fit and operation in all three positions in case I need to move the bars forward or aft after the seats are installed. Opened up center support mounting holes as needed.
-Determined I need to use a AN960-10 to as a spacer for the two side mounts that I cut in half. Determined I need to use an AN960-10 and a AN960-10L for the center mount.
-Identified where the rudder bar and/or brake petals hit the firewall stiffeners and determined I can use an edge grommet and/or split hose to protect the firewall stiffener.
-Measured the side play of the rudder bars in the most forward and aft mounting block locations. The forward rudder bar (right rudder) has almost no play in the most forward position and only 0.094" play in the most aft position. I consider that to be perfect since it allows the rudder to be able to mounted in any mounting block location with minimal side play. The left rudder bar (left rudder) has 0.094" of play in the most forward position and 0.186" of play in the aft position. I'm going to order some plastic to make a spacer to keep the max left rudder bar side play to approximately 0.094" to match the other rudder bar.
-Rechecked the movement of the center rudder bar support bracket now that it is riveted in place. The bracket movement is barely noticeable even when pulling on it with 20 pounds on the side where the TWC backup battery is installed.

Tested the right pilot master cylinder using emailed instructions from Matco (Compress the shaft and then allow it to extend. Lay the cylinder on a table with the ports up. Fill the port near the shaft [I used a syringe to keep from making a mess with the Royco 782 fluid]. I noticed I had to keep adding fluid slowly as the fluid flowed through the cylinder. Verify the fluid eventually starts flowing out of the other port. Cap off the other port, change the position of the cylinder to shaft up. Compress the shaft and verify it becomes firm with only about 1/8" of movement, that there aren't any leaks around the shaft and that the shaft does not slowly move under pressure). The test results show it was working okay.

I had previously disassembled the left pilot master cylinder using the Matco maintenance documents. I didn't test it before disassembly. I used a rebuild kit and reassembled it. I noticed the original seals had taken a set and were not as flexible as the seals in the new kit. I'm going to rebuild all the master cylinders while they are easy to reach and I don't have fluid in the lines that will make a mess.

Looked up documentation from Van's and vansairforce on thread sealant and NPT fitting torque. I'm going to use Loctite 567.