The threads inside my square slide dellorto's off my ambassador have stripped out after 50 years and 100,000 MI of service and repair. It's a threads that hold the needle jet and accelerator pump / main jet tube. They are a 12 mm by 1 mm thread. Has anybody had any luck repairing this? I'm looking at a helicoil repair kit let me know if anyone has had any luck with this repair .