I need to specify a hole (to be drilled and Reamed on site) for a tapered dowel Dia 10 x 60 long DIN 7978 taper 1 in 50

The dowels are to locate rack sections along a beam once they have been correctly positioned, the racks have a pre drilled dia 10 hole.

Has anyone had experience of specifying such a hole?

Help gratefully accepted.

Regards Derek.