I wouldn't recommend doing the metal shimming on
any shifter. Instead, if you have a heat gun, simply use some heat with a bit of dimensional restraint, to re-form this thermoplastic part until it arrives at the desired clearances.
It's so much easier, and more reliable than using a metal shim, (which in my experience, even on the stock-style shifter, was very difficult to install, very likely to come out, and in the very slim chance it stays put, could be prone to having longer-term lubrication/wear issues.)
Removing the plastic piece may be safest approach, I found it's possible to reform the dimensions of this bellcrank without full shift console disassembly (it's not a bad idea to use foil to block heat getting to areas you don't want to heat up too much, and warp). You can remove the pivot pin, you can get it up where you can flow some hot air to it. I used vice-grips (lightly clamped on outside before applying heat) to restrain expansion motion, and found upon cooling/contraction, it very nicely tightened up the clearances. I used the least amount of heat to get it to reform. I did this a while ago on two shift consoles (one spare/experiment, one I'm currently using), and I saved the attached pictures...
With the grooves already worn into your existing plastic bellcrank, you basically have this piece already "broken in" to your aftermarket short shifter ball, and you might even find after a repair, it lasts longer than it did before.
Definitely put in a generous amount of plastic-compatible grease in there, to try and give it a fighting chance of lasting longer with your aftermarket short-shifter. I'd avoid a conventional oil-based grease, due to risk of it attacking over time the plastic material. DuPont Krytox is good, silicone grease is fine and likely what the factory used on their plastic shift consoles.
Or you could go back to one of the stock-style shifters, but even those will also benefit from being "tightened up" on clearance reduction from this heat gun trick! I think they are made with an excessive amount of clearance on this area (why they are made that way, I have no idea!) so even a brand new one will benefit some from this blueprinting "trick."
Hope it helps... best of luck!