For LA motors the 318/340’s have the larger rear radius seal area, the 360’s have a smaller rear area. Good discussion on the differences with pics here: Spotting the difference between 360 & 340 Oil Pan
For magnum motors the pan is the same for 5.2 and 5.9, same p/n’s for magnum pans at Summit or Mancini
Picture is a 340 engine showing the larger rear cap on the engine with the 360 pan having the smaller radius.