steering coupler questions

As you might have seen I couldnt find my new rebuild kit the other night. I have found it and when I went to install the new parts I found that the original pin that goes thru the shaft had a diameter of .335 and the new one is .330. That means that the new pin wont be tight so I cant use it. Now the 2 new sliders wont slide onto the old pin as well. The old sliders are actually tight in the coupler so I am ok reusing them. I dont have a drill bit that will open them up without making them loose. The next thin is what are you using for the grease that goes in the coupler and how much do you fill it with. My coupler will be going thru the TTI headers so I expect it to get a good amount of heat. I dont want the lub to liquidfy and run out.
Thanks Rod