I have been going through this forum with great interest as I have the same challenges...small sheave holes that are a part of the block, which may or not be the correct size and a rope indication that may also be the wrong size. The advice given through this forum is great advice for both the rope and the block. But, I have what might be considered a 'third' question: how do you hold a 2, 2.5, 3, or 3.5 mm. block so that you can get the mini drill bit through to enlarge the sheave hole to accept the 'frozen' rope? I have tried the following: fingers...not good for me as I am a bit ham-handed; hemostats...the smaller blocks seem to crush too easily: clips or pincers of varying sorts...hmmm! when the block flips out of a clip, it takes off light a jumping bean, never to be seen again. (I am very glad for Dry Dock blocks). However, and a bit more seriously, what is the secret to holding those little things firmly enough to adjust the size without ruining or losing them?