Alan,

I may be mistaken but I thought the oval hole was for the reverse and air grabber switches? If this dash panel came out of a non grabber car they may have drilled the reverse hole offset.
Also, I believe the white block with the nipples is attached to the panel with the bezel screws.In other words, the plastic panel is sandwiched between the bezel and white block.
The solenoid was used to dump the air from the actuator when the car was shut off and the spring from the actuator bracket to the flap linkage would pull the door closed.
If you leave the solenoid out and leave the spring off the door will stay open when the car is shut off.