I am sorry for my steering malfunction hijacking another post, so I am moving this out on its own.
To recap, I have the Borgeson power steering box conversion on my 66 coupe. I love it, but the upper steering shaft came out while I was entering the freeway during rush hour. I managed to avoid hitting another car, somehow, and was able to get home safely. After changing my shorts, I fixed the shaft by drilling a hole for the set screw through the splined portion of the shaft.

I send Borgeson an email about my story and they replied in less than an hour with an actual response. I thought you might want to read along.

My (polite) email to them:
I have the power steering conversion kit #999020 installed on my 1966 Mustang for a little over a year. It has been a great system, and I tell everyone I meet that they should install it on their car.

A week ago, I was entering the freeway and the upper shaft pulled out of the rag joint while accelerating. I managed to stop the car without getting hit (after crossing a few lanes uncontrolled), and I was able to put the shaft back in the rag joint to get the car off the road.  When I got the vehicle home, I noticed that the set screw on the rag joint had completely backed off allowing the shaft to pull out. I could see an indention in the splines from the setscrew, so I know it was tightened during installation.

I drilled a 5/16" hole 1/4" deep in the shaft to allow the set screw to hold the shaft better, and I used locktite blue on the threads to prevent it from backing out again.

Looking at the directions again, they do not mention drilling the shaft or using a thread locker on the set screw. I did notice that the steering box has a groove milled in it to accept the setscrew, however the upper shaft has no such modification in the splined area.

I randomly reviewed several other product instruction pages and they encourage, or require, a hole or flat spot for the setscrew. The background picture on your webpage even shows a splined shaft with a flat spot milled into it for the set screw.

Could you please modify the directions so that other customers will not be placed in the same predicament as myself. Even still, I speak highly of your product and recommend it as my preferred steering solution for the Mustang - with an additional warning for installation.

Thank you,
Bob Nettles

Their response:
Good Afternoon Bob,

First thank you for using and recommending our products, our customers are our best brand ambassadors and we appreciate it.  I apologize for the harrowing moment this must have caused.  I do understand the issues you had and the conflict between the catalog and instructions and will work to have the column shaft instructions changed to reflect this. I am additionally investigating a manufacturing change to the shaft itself to see if I can get manufacturing to perhaps put a similar groove in the shaft to completely eliminate any issues.

Thank you again for your feedback and recommending our products.

Thanks,

Jeff Grantmeyer
Sales Manager