There is a post here or maybe I have it on the Cabe of the instructions for the PVC rack. All slots.can be altered by lengthening the spacing pieces. I don't glue mine together so I can add sections to lengthen it for my wider trailer.
I do have the instructions on one of my gallery pages titled " bike transporter" on the Cabe.
It's all about the Tanklights!!
How did I run out of room so fast?