oops! i just came across some really old designs when i was "planning" on doing this with my arb bar...hopefully it helps some of you.
Below is from left the front of the hilux chassis rail layout, middle is the arb mount plate to suit and on the right was my proposed sandwich/adaptor plate to raise the arb bar 2" higher.
to go along with this idea i took a pic of my then arb bar and tried to work out what else would need doing -
the green highlited section would need to be trimmed off to allow it to go up higher.the bottom hole in red would fit the next hole location up, not sure if this was 1 or 2".....
the other method was to leave the actual mounts as they were and to make a spacer plate at the front of these mounts to raise the bar itself higher -
diagram below is an old dodgy diagram but you get the picture -
spacer plate would look similar to below -
so it'd mount at the bottom to the front of the arb mount itself and raise the bar higher leaving the mounts as is.
the third option i had was to ditch the arb mounts altogether and get some proper pabbed up mounts to suit the bodylift without any of the crush tube area and make it look the part -
so it'd completely replace the arb bar mounts themselves.
hope that helps, im sure there are other ways to do it but these were my 3 first options before i ditched my plans for a bodylift.