Rich,I used the complete front susp. from a 77 chevy half ton
short bed,it was a near bolt in,the susp. bolts to the
crossmember the crossmembers bolt in the same way.
All I needed to do was drill my holes out to half inch size
and locate the idler arm on the frame rail,this last piece is the tricky part but if you take careful maesurements it comes out fine.
The 66 frame is a direct change over,one other thing I noticed
was that the frame rails were identical between my 65 and the donar 77 i would have used them but they were short and mine is long. hay wagon