If you start manufacturing parts for 3rd gen guns, you may need a wheelbarrow to carry the money to the bank.
The nervous nellies here alone should keep you busy the first year. There seems to be a fascination with spare parts, or the percieved lack of them.
I don't understand it as in 30 years of shooting 3rd gen guns, much more than the average enthusiast, I've broken 3 parts. A mag catch on a 4516 made of cheap MIM, a sideplate which lost a prong after 9K rounds through the gun and a nylon value line mag catch which wore down - in the same 9K round count gun.
But I like the decock only feature and have it on my 4566s and my carry 4513TSW. If you start making the parts I will buy at least two sets to convert my 4506-1 and a LNIB 4513TSW I found in the safe. Good luck! Keep us aprised of your progress! Regards 18DAI