leica cl-help to get 28mm framelines

[rbelyell]

thank you in advance for what i assume is an easy answer to a pretty basic question: i have a 2.8-5cm leitz m39>m mount adapter that brings up only 40/50mm framelines on the cl. i noted from looking on ebay that all 28mm adapters seem to be 28/90, but putting a 90mm m mount lens on the cl calls up 40/90 framelines, not 28/90!

so what do i do to call up the 28mm framelines?

thanks
tony