You can make the 16v fit the 20v so long as there's enough metal there to drill the new holes for the end bolts, the centre 3 line up.
I'm not sure if he still does them but anthony @ kaizen garage used to make multifit stainless versions
Phone 0415 185 815#sales@kaizengarage.com
Looking through the old thread, looks like you hit him up a few years ago in regards to some.
Either way, hope that helps!