I scrubbed and refilled the shocks and mounted them to the suspension arms.
So, the only issue I had with the vintage parts was D4. Apparently, this is a very common issue with the falcon as Falcon#5 pointed out. I decided to use JB Weld Plastic Bond on it because I have some experience dealing with that kind of epoxy in the past. It worked like a charm.
I had to sand away some of the overflow but, after a good 24-hour clamp, even the torque of a 3x12mm self tapping screw didn't break the bond. Of course, we will see once it starts running.