RETRO FIT 68 to 88 WIPER MOTOR
 

This is how I made a 88 wiper motor work in my 68 GMC. You may ask why? I wanted delay wipers and was installing an 88 tilt column w/wiper controls anyway so what the heck! Plus the 88 motor mounts flat to the firewall which gives more room under the dash.
1. Remove old motor, then drill the spot welds to remove the old mounting dish.
2. Make up new mounting plate for 88 motor, I welded the bolts to the plate for easier installation. You will have to cut a hole in the firewall to get the room for the 88 motor.
3. Make new motor crank. Measure from hole to bellcrank on the 68 crank, cut the 88 crank in half, you have to use the hole from the 88 and the crank end from the 68. Measure, cut, weld.
4. With the motor mounted to the new mounting plate, bolt the plate to the firewall, Use the rubber donut gasket from the 88 over the shaft to seal out the water, I used plenty of silicone to be sure I had a good seal, install the crank, in park the crank points to the drivers side, hook up linkage and be sure everything works without hitting anything.
5. Use a piece of sheet metal to make a cover for the hole you cut in the firewall, I just glued it in w/silicone for now until I have time to weld it in.
6. Plug in the motor and drive happily ever after.

Re: RETRO FIT 68 to 88 WIPER MOTOR
 

Well alrighty then Arkie. Very good information for me. Been thinking about a different wiper motor just to speed up the wipers. Good job. Larry

Re: RETRO FIT 68 to 88 WIPER MOTOR
 

This is what it looks like on the outside.