The dimensions of the screws that come with the kit are 31 mm x 35 mm x 27 mm.
Do not tighten the screws until all of them are in place. Once all eight screws are in, go back and tighten each one. This is done so that the new tuning keys can be properly aligned.
I just bought this exact guitar at an estate sale this past weekend I bought it for my granddaughter to learn how to play the neck has a little bow in it and I was wondering if you knew what size the adjustment screw is and what type head it is.