What is needed - Probably nothing, IMO.

That said, I cannot leave it alone. I massage the inside radius of first right angle encountered in the block on the suction side. Clean, radius an enlarge everything in the pump including the oil filter fitting. I've posted before the significant misalignment in the Melling pumps between the pump body and pump cover on several pumps. Probably a 25-30% crossection reduction due to the misalignment between the two pump halves. Hopefully they fixed it, but you should check.

Then radius and enlarge the the pump and block pressure side transition.

If the hemi pan fits, use it with either pickup you want. I use 1/2", May not in the future. Slight mod of the 1/2" and it worked fine. Full length, std stroke Milidon standard stroke windage tray, inexpensive girdle, scraper, and it all tucks up real nice.

I use a standard volume pump, full time unrestricted rocker oiling, with 0.003/0.0025" bearing clearances and have good oil pressure.