Looks like you'll get the job done just fine, as long as the dreaded buck fever doesn't take hold.
My younger brother opted them same sorta thing a couple years ago, only he went with a Cowboy Marlin Octogon barrell lever gun , tang sights shooting hand cast 'cowboy' loads in .45-70. And mind you he's an excellent shot, but when a decent buck came into view... well it finally dropped with 3 big ol holes thru it's lungs.
I'm curiuos, What kind of loads are you using, any special bullets?