Orientation of my solids on sloping surfaces

Hello all. Basic stuff but I am having a lot of difficulty in acquiring the correct orientation when trying to draw a cylinder. On the right view of the attached I am trying to draw 4 cylinders around the extrusion, (at the intersecting points on the outer circle), but through the sloping plate.
There doesn’t seem to be any way that I can achieve the correct orientation.HULL - Copy.3dm (58.5 KB)

Make a custom CPlane (see help) by setting it to the circle. Then just draw the cylinders at the intersections.

Yep, easy when you know how. Many thanks again!