Drilling Hinge Pin Holes Adviced Please

[Richie-Van-GTi 70 2 Cars]

My hinge pins were basically fubar and the holes dont appear to be exactly round anymore so I bought some 9mm diamter roll pins, standards are 7mm. I know these will have to be drilled out anyway so thought Id get some nice tough ones.

Do I drill the hole to 9mm or shall I go for 8.5 as the pins should reduce down to that as there is a 2mm gap in them which allows it to reduce enough. Also should any part of the holes be slightly different to allow for movement in the hinge?