M Lenses iR Focus point

Hi,

I’m using my M10 Monochrom with a Summilux f1.4 35mm and a second hand 135mm for infrared work and am having trouble locating the correct iR focus points.
Can anyone help me out with this, not had much success with this either at the Leica Shop in Düsseldorf or on the Web.
Sure would appreciate it.