Years ago I worked up a load for my best friend, that used the Nosler Solid Base seated over 58.5grs of IMR - 4350, Winchester cases, Win-WLR primers and an OAL of 3.250".
This load dropped everything he ever put it to task on, and generally kept groups at or under 1" at 100yds. I have also shot this same load in several other rifles of different makes and models and the results have been the same. When Nosler dropped the SB and went to the Ballistic Tip I followed suit with his load and the groups actually tightened.
For nearly 15 years now I have been using this particular load, working it up in various rifles and coming right back to about the original specs. The seating depth might be off by .010 one way or the other, but close enough still it would shoot VERY acceptable. I have tried other bullets along the way as well, and have seen it shoot well with them also, only the powder charge might be down a grain or so. This load has constantly ranged in the 2850fps range in just about every rifle I have shot it in, and pressure has never been an issue.
As for the 165gr bullets, I have found RL-22 to function the best with them. Gives top end velocities, and great accuracy. The only issue I ever had with it was a load I worked up in temps around 65 - 70 degrees, when the temp dropped down to around the low 30's the primers didn't want to light it all off. By the same token, when temps hit the upper 90's it would flatten primers. However looking at the Hodgdon load data, it shows virtually the same load using the H-4350, which I know is very stable, and it should work out fine. I simply haven't worked much lately with the 165's, since the 150's suit my needs for most hunting I do.
Another powder which has shown promise with several other calibers has been the Ramshot Hunter. I have found it produced excellent velocities, and accuracy in several other calibers we have worked with. I plan on working up something using it this spring, and looking at the data, and based upon the other calibers it should work great as well.
Good luck with your trip and your loads as well. I have had a hankering to go to the Senoran Desert for on of those big mulies for quite a while. Just seems other things keep pulling away at the funds.
Take Care,