TR2/3/3A steering box tr3

I hate to show my frugal Scottish side, but does anyone have an idea or solution as to fixing small chips on the worm gear in the steering box of a tr3. I suppose they can be polished out, but I think that would add some play. And clearly a new one would resolve the problem. I see that they are available, but they have to be welded to the old shaft. The metal appears to be very hard cast iron. Perhaps with some extra carbon or something in it; I do not know. I guess, I am asking if the pits can be brazed then polished.
Sp53

Actually, I believe the worm gear is press fitted to the shaft under heat. There was a thread on this subject somewhere not to long ago from a guy in the Netherlands who had his replaced. I will try and look it up. I don't think you can fix a chip in the worm.

This is the link to the discussion and eventual replacement of the worm gear on Mr. Betzels car.

https://www.british-cars.co.uk/cgi-bin/ge...040718222414282

The following is a discription by the owner of the process of removing the old worm and installing the new worm if the link doesn't work. You may have to sign up prior to entrance. While the process sounds easy I would guess its harder to get right than it looks and you will need an experienced black smithy to do the install.

Wim Betzel, Netherlands
Hi all, ok the salesman told me it is piece of cake to replace the worm. Well, his brother the craftsman was not pleased on first attempt, because the old one didn't come off easy. His press is to short for the Rigid (one-piece adjustable) type column i have. The end of the rod is conical and holds the worm tight on the column which has a splined end. Because it was to late a had to leave it in the shop, so no pictures alas. Whats the trick. You need a heavy piece of pipe a little bigger in diameter as the column. Slide this pipe over the column and catch the end of the column in a good bench-vice. Then heat the end red hot and knock the old worm of with the pipe. So don't file the conical end of, because after installing the new worm you need to fasten it on the column again with a conical punch! A weld can brake easely when you hit a pavement.
Next monday i will pick up the column, so i can take some pictures.
Regards, Wim.