As for the widths, they are shown in this document from Air China
They make the holds to fit the standard containers. They fit fairly tight but there's a little room around them.
The outside height of an LD3 is 162.6 cm. If you look at the top diagram, on the right you see they have that marked (as 163 cm), therefore 171 is the height of the hold itself. There is 8cm of clearance above. On the left, PAG and PMC are pallets, or "cookie sheets". You stack whatever you need on them and cover it with a net, so 171cm would be the limit to how high you can load it so that it fits into the hold, except that the document lists the door on the front cargo hold to be 170cm and the aft to be 168 cm. So whatever you stack on a pallet has to fit through the door.
The bulk cargo hold is an irregular shape, so exact dimensions won't be given. But that Air China document indicates that they are 511cm deep and have a volume of 19.7 cubic meters.