'65 904 Torqueflite: No Start in "N", no forward or reverse.

bypass neutral safety switch. I bet the comb is not hooked to the push/pull cable properly. There is an adjustment procedure built into that cable trans at the enterance. hit the start circuit and hold it while moving the shifter slowly and see if it catches.
Mopar Push-button transmission tech tips

"GEAR SELECTOR CABLE ADJUSTMENT

The gear selector cable is attached to the selector lever in much the same manner as with a push button box, with a cable eye over a pin, secured by a flat washer and spring clip.

The removal and installation procedures for the gear selector cable at the transmission are the same as those followed with push button cables, but the adjustment procedure is different. To make this adjustment, proceed as follows:
1. Have an assistant hold the selector lever firmly in the "1" (Low) position.
2. Hold the control cable centered in its bore in the transmission case, and pull outward on the cable with about two pounds of force to bottom the manual lever in the "Low" detent.
3. While maintaining this pull on the cable, rotate the adjustment wheel clockwise until it just contacts the case squarely. 4. Turn the wheel counterclockwise just enough to make the nearest hole in the wheel line up with the screw hole in the case.
5. Counting this hole as number one, continue turning the wheel counterclockwise until the fifth hole lines up with the screw hole in the case.
6. Push the cable in toward the transmission until the adjustment wheel is tight against the case and install the lock screw, tightening to 75 inch-pounds torque."