Pioneer2
If'n it were me and I know it is probably to late, but i would load up the 1/48 with 90 grains of T7-3f, then a .510 x .125 Shot Card and either a 460 Bull Shop conical or a 460 No Excuse Conical.
But when it gets right down to it your listed load has done the job in the past for a lot of people - just reduce the range as much as possible and put it in the right spot.