Mark Houlahan
Tech Editor, Mustang Monthly
March 14, 2014

What we ordered

'65-'66 Power Top Switch Under Hood Feed WG-105 $13.95
'65-'66 Power Top Switch to Motor Feed-Left Side WG-106 $37.95
'65-'70 Convertible Top Hydraulic Cylinder (x2) ST-164 $139.95
'65-'73 Convertible Top Motor ST-1647 $199.95
'65-'66 Convertible Top Motor Mounting Bracket ST-16471 $26.95
'65-'68 Convertible Top Hose Set ST-167 $89.95
'65-'66 Right Shock Tower Wiring Clips PE-4801 $4.00
'65-'66 Convertible Top Switch ST-157 $41.95
'65-'66 Convertible Top Bezel and Knob ST-1591 $32.95
'65-'68 Convertible Top Junction Block w/ Fuse Link ST-156 $19.95
Total $747.50

13. Moving on to the hydraulics the counter balance springs need removal next. The springs are at their lowest tension with the top up, so raise the top if it is currently down (no need to latch it) and remove the two bolts (per side) retaining the counter balance spring pivot bracket through the angled access hole in the well frame. You can see this hole in captions 4 and 7.
14. Reach up into the well frame and remove the pivot bracket. Keep the bracket handy, as it will be reused for the hydraulic ram installation. Reach up into the frame a second time and grab the counter balance spring and pull it free from the outboard pivot point. Lastly, remove the retaining pin and washers from the spring’s connection to the top frame to free the counter balance spring assembly, and then repeat for the opposite side.
15. The key to the power top’s conversion are these hydraulic cylinders mounted in place of the counter balance springs. Using hydraulic pressure the rams are either extended or retracted to move the top into an open or closed position. Shown here are Virginia Classic Mustang’s U.S. made versions. They’ll run you about $50 more per side but use higher quality internals and are exact replacements, not universal, and feature a 3-year warranty.
16. A hydraulic system like the Mustang’s power top requires hydraulic lines with specific fittings. The easiest solution is to pick up a set of Virginia Classic Mustang’s direct-fit line kits. The lines include the proper fittings and length and drop right into place. The short line is used for the upper cylinder fitting, shown here, and should be secured before the ram is installed.
17. Install the new hydraulic rams into place on the pivot pins and reinstall the pivot bracket and retaining bolts to secure the assembly. Be careful to ensure the ram’s top shaft is properly positioned in the top stack assembly (you might need an assistant to lift the top up slightly to seat everything). Once the rams are installed you can route and connect the longer fluid line to the bottom port on the rams.
18. You certainly won’t need the manual top’s hold down brackets anymore. These hold downs engage the end of the top stack to hold it in place when the top is down, but the hydraulic components will keep enough pressure on the stack to prevent movement/rattles. Simply remove the two retaining bolts (per bracket) and place them in your spare parts pile.
19. Virginia Classic Mustang carries top motors from All Classic Parts (ACP) in California. ACP’s top motors are known for their quality and fit and come with the correct wiring connections and mounting ears. Connect the hydraulic lines to the pump; the lower hose attaches to the front of the pump and the upper attaches to the rear of the pump (with the pump’s wiring pointing to the driver’s side).
20. Fill the top motor with ATF per the included instruction sheet, leaving the reservoir about 25 percent empty to allow for fluid movement while bleeding the system. Have a helper manually raise the top and then reconnect the battery. Your helper will then need to move the top switch up and down, a few seconds in each direction, to start pumping fluid through the lines.
21. After filling and pumping the system a few times you’ll start to see the hydraulic rams move in and out. Run them out to their full extension but no further. There are no internal stops and you could push the rams apart with pump pressure. Now bring the rams all the way in until they seat. Repeat this process a few more times until the fluid lines show no air and the reservoir is at the proper level.
22. Run the hydraulic rams out far enough to attach them to the top frame using new retaining pins and bushings (the counter balance spring hardware is different, so be sure to order the new bushings and pins with your hydraulic parts). Test the system one more time, now opening and closing the convertible top itself.
23. Once the system is bled, the top is connected and functioning properly, and there are no leaks you can mount the pump. Your Mustang should have these threaded nut inserts already in place. If not they are available from Virginia Classic Mustang.
24. The one elusive piece to the ’65-’66 Mustang power top conversion has been the power top motor mounting bracket. It is now finally available in reproduction and we were lucky to get one of the first ones from Virginia Classic Mustang. This bracket bolts down in the well area to provide a mounting point for the electric pump.
25. The four mounting points of the motor include two rubber push-in feet and two rubber isolators secured by nuts and washers. Lubricate the push-in feet and then place the motor into the bracket and give the motor a push/wiggle motion to seat the feet into the bracket. Finish the installation of the motor by securing the front mounting with the proper nuts and washers.
26. Secure the hydraulic lines using clamps adjacent to the motor opening in the well frame. We added a few sections of tape just like the Osborn manuals show to prevent chafing over the edges of the well frame as well. Reinstall your seat and quarter trim, door sill plates, and kick panel and you’ll be ready for your next outing to drop the top in style.