I agree with WyoJoe.

If it were me, I'd be taking my 300 H&H Ruger #1 (sighted to 250-300yds with 1.75-5 scope) and my .375 H&H BRNO 602 (with iron sights regulated to 100yds, and low-power 1-4x, if needed, sighted to 200yds in QD mounts).

Sometimes the old forumlas work. The 300/375 combo was the classic British 2-gun battery for Africa. If a third gun was brought, it was likely a custom .303 Jeffrey- or Rigby-Lee Speed Sporter, or possible a .275 Rigby. (The PH, of course, wielded the heavy artillery).

In any event, you don't want to bring along 2 rifles chambered for cartridges that are near-duplicates of each other. And your decision should be guided by the range of species you intend to hunt.