Here is a set I fab'd up about a year and a half ago, used 1.750 mandrel u-bends from speedway with 3/8" thick flange plates. did each pipe in 2 pieces in order to change direction & get the angle I liked then tig'd them up. my rail is 1959 so I was going for a more period look rather than a zoomie.
here is a progression of headers on my rail, 1st pic was early 90's with long swept out weed burners, next I borrowed a set of up swept zoomies from a buddies mid 60's C/D, then I built the set I put on recently.