I am fortunate I have the previous charging handle locking pin.
A little irritating without a long slotted screw driver, but doable.
I saw the new locking pin, but after acquiring it, realized the difficulty in assembling to the recoil spring.
You even acknowledged the possibility of some being unable to complete the assembly. I am one unable to compress the spring.
Here is a blog post on working on the recoil spring, and a method to compress the spring.
Several other sites call for a replacement spring rather than messing with the spring.
I suspect you may receive some feedback on the difficulty of this modification, and maybe some dissatisfaction.
I hope you will still manufacture the previous locking pin as an alternative for your customers.
As an option, if you purchased recoil springs from Kel Tec, at $9.45, and performed the modification in house, you could sell a pre-modified tool less locking pin recoil spring.
The recoil springs are available here:-