I know you can use 82 idler arm not sure about power-steering the 66 frame is flat where the power box mounts, the CPP adapter spaces the box correctly off the frame. If you bolted the power box up without some sort of spacers, either the frame will crack or the box will break because of the bind.....no way around not using the adapter for the correct mounting unless you cut and weld the frame for the later box to clear
[email protected] can answer your questions and makes this bracket is $55.00 plus $7.90 for shipping in the USA.
hope to have power-steering soon