You need to line up kingpin then engage threads of oiler bolt by hand before even considering tightening with spanner or socket. I've found one side will engage on first attempt but other side will be a PIA. Strangely this seems to follow through with many aspects of car maintenance
Having an alignment tool close to minor diameter of kingpin thread helps, I use a tapered drift. Leaving BRB (if you have them) chassis fitting very loose also helps, tightening only after oiler bolt fully engaged.
