Here it is before I lengthened it. As you can see, the shifter boot came loose.

Use a small screwdriver to pry the little cap out of the rubber head. Pretty easy to do, just get under the lip.

Then undo the bolt, then after that you have to also unscrew the knob as it is threaded to the shifter.

You can see that it is threaded

My boot was depressed for so long, I now have to replace it as it is torn and does not fit into place any longer.

Here are the parts I used. The top nut on the right is the one that was on the shifter. I then got another one the same size and threads.
The bolt on the left has threads identical to the threads on the shifter. I cut the head of the bolt and discarded it.
The small pipe in the center I cut at three inches long as that is how far I wanted to extend the shifter.

I inserted the bolt into the pipe 1 1/4". This measurement I got from measuring the threaded part on the shifter itself. This is the part the rubber knob threads onto later.

The nut on the right is the one off of the shifter. Once this is welded in place, it will thread down upon the shifter.

I used a mig welder to weld it all up. Then used a tiger disc on the angle grinder to grind the welds down some. The next step is to taper the end up by the threads.

Here is a close up of the tapered end. I tapered it on a bench grinder. I would fit it to the rubber knob, then taper it some more until it fit right. It helps if you spray a lubricate into the rubber knob so this part will fit easier.

Once you screw the rubber knob on, put the second bolt on and tighten it down. Then stick the new part through the boot and thread it onto the top of the shifter and tighten it down real good by hand. Then you can pull the boot up to the bottom of the rubber knob. Then place the plastic plate back into the top of the rubber knob and you are down.