Jeff:
I made one last year out of 1and1/2 PVC.
It worked out really well,even in a really nasty run .It doesnt mark up the cork
grip ar any other part of rod .I tested it with a real clunker rod I had and it seemed fine and have since transported many top end rods of friends and no problems or complaints.
1 1/2 in PVC appx 16 in long ,cut slot just slightly wider than reel base ,appx 12 in down and taper slot at top for easy insertion , the width is key. Spend some time filing and sanding edges of slot.Mount on vert surface (mine is on front of console on top of seat) and adjust so that slight intercept angle to vert surface ,( this keeps rod snug to vert surface)and thus no whip.
No complaints from the Sage yuppies yet ! :)
Dave