We always cable them at the top first before doing anything and then hook that to a dozer making sure we have about 50% longer cable than the silo is tall, we hook it to several bands in case one or two snap, we don't use the top most ones either, about 5-10 feet from the top so it doesn't pull the top few rows of staves off, then you have something hooked to the silo to help give it directional fall and also in case it decides to just do a dance and sit back down on its staves again and do nothing, you can still give it a gentle tug and over it comes. A lot safer than guessing what it'll do and where it'll go, never yet had one go somewhere I didn't want it to or hang up and just sit at some weird angle. We also use a dozer and chains to pull the wedge out, that way once your set up, nobody is even close to the silo, also making sure you have enough chains to be far enough away to start with, as for taking bands off to allow for a larger wedge, that depends on the silo and what condition its in and what kind of staves its made out of and use your best judgement as to whether you do that or not, sometimes we do other times not. I've sometimes used several cables to pull them over, hooking them to several different set of bands towards the top and have someone standing outside to direct traffic as to who pulls and how fast to pull but most times you only have to have the cable dozer drive maybe five or ten feet and the silo is down laying on the ground. By far the safest way to do anything I've ever found, that way nobody is even close to it if something goes wrong and you have some control over where it goes and how and also if it starts to dance as it comes down you can speed up the dozer to get it to stop and just fall where its supposed to go, no different than pulling a tree over with a cable as your cutting it after making the notch first, with the leverage you have hooked up high it takes very little effort to get it to go where you want it to, and out of the thousands of tree's we've cut down we've never had one we cabled go the wrong way and nobody ever has gotten hurt either, it takes good communication and have those doing the operating do what and when they are told to do it and have one person directing traffic and giving orders and if something ever would go wrong at least nobody will get hurt, things can be repaired or replaced if something weird happens but if nobody gets hurt or killed consider it good day and move on and learn from the experience.