The process I used for this does not involve welding. While I think using a welder to do this would be quicker and probably have a better end result, I don't have a welder. So as an alternative I took this approach.
Here is what I started with.
I ground out the welds holding the right "mount".
Put the assembly in a vice and cut the right "tube"
I then drove the mount into the tube.
Once I had it positioned, I did the same on the left side.
I mixed up a batch of JB Weld...
...and using a putty knife, goobered the epoxy into both ends of the tube, cleaned up the mess, and taped off the ends while it cured.
This is what I accomplished on day one. As JB Weld takes 15 hours to cure, I went on to other things while it cured.
Earlier, when I dry fitted the pieces prior to potting them, I determined the correct length for the spacers and set them aside. Getting back to them while the JB Weld cured, I rough cut them to within an eight of an inch of their finished dimensions. As the mating ends are not parallel, I used a table top disc sander to finish it to the desired length maintaining relative angles of the ends.
Here's the finished spacer with the wasted piece.
The difference between Genius and Stupidity is that Genius has its limits.
He who sacrifices freedom for security deserves neither.
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