A small, but very effective tip for easier plastic injection molding set up is to standardize the clamping slots on the top and bottom plates of all mold bases. This little trick might seem obvious, but it is surprising how many custom molders have every size imaginable in their mold base inventory.
With this method you need only one size clamp, which can be custom made or likely purchased. The set up techs won’t need to be fumbling about for the right size clamp, there will be no shims under clamps and you can be sure the molds are held in place securely.
This is also a good idea from the standpoint of training. There is enough to learn without adding another item to the list of how to set up a plastic injection mold. Once this is in place, it will quickly become a SOP, standard operating procedure.
All your future designs must have this incorporated, which, for some reason, is not as easy as it might seem. You likely will still have the occasional mold that comes in the wrong size, but in time they will all be standardized.