My biggest achievements in such endeavors are tiny homemade springs (brought back to life some "beyond repair" surplus handguns), and HK TRS tool ala https://www.hkparts.net/shop/pc/Trig...-198p16031.htm.
I am afraid if I try doing that on my lever I will turn it from sausage to brute-axe-butchered sausage. :-)
Still, for someone who can do it precisely, that is the best suggestion, as it will keep the proper geometry of the rod.
On behalf of those guys, thank you.