Lo-Dapt II thread adapter?

Hey everyone, I was wondering if anyone has the Lo-Dapt II from Gennie Shifter and has found an adapter to go from large to small threading. Everywhere I look I see adapters to go from small thread to larger threading but I can't seem to find one to go the other way. I bought a custom shift knob and my dumbass forgot to tell the guy the thread size so he made it with what looks like the smallest damn hole I have ever seen on a shift knob. Any insight would be greatly appreciated, thanks everyone.

use a helicoil insert?
I've found Ace hardware to have a good selection

Maybe weld some nuts and bolts together so you can make it right.

If its too small then you can always just drill it and retap it..