I had the same problem with that zerk and posted how I decided to plug the hole and swap out a zerk during service. 56FordGuy suggested a needle fitting at that time, but I had no luck sourcing one locally. I did talk a local who who would drill and tap the pin as suggested by SuperGlideSport, but I was too cheap to pay 50 bucks to have it done.
I've serviced the backhoe three or four times since that post and the extra few minutes it takes to swap the plug and zerk hasn't decreased my life expectancy significantly, so I'll continue to do so. The 260 BH is a beautiful piece of engineering, but I can't imagine what they were thinking when they placed that zerk at the end of the dipper stick. :cookoo: