Yes they are m3.5 mm screws what I have done is bought the 5x40 torques head screws for still guns ran them through a 3.5 mm die they come out perfect. When I thread them I only go as far as needed leave the rest the original thread diameter it takes up the slop in the hole.lok Tite them in if you need to remove them get a small butane torch like the novelty ones you can get at any c-store heat the head and the inside of the frame they come right out. It's worth the money to get the correct torques plus bit for removal it's not a normal torques bit is a torques plus any snap on or mac or matco dealer will have the or order one online. And yes I have a vista short and had the same problems. The other option is to have your frame drilled and taped to the 5x40