From memory, AC isn't ridiculously heavy, and certainly lighter than cast. (You could start with the Hopper and downpipe to get a feel for the stuff perhaps?)
Cutting is a big NO NO, that will create dust, and release fibres, which is the very thing you need to avoid. If you absolutely must reduce the lengths, I would break them, dampen down as best you can before doing so to reduce risk of releasing fibres as much as possible. Given you're not supposed to break it unless absolutely necessary, I was amazed when the Licenced Contractor I engaged to remove my old AC garage, smashed the thing to bits before loading it on his van!