Rope rear main seal in early engine

[Shoebox]

So at some point I am going to go through the original engine in my 39 Merc. Although it will remain stock in outer appearance I intend to use my 4" crank and 8ba rotating components. Regarding the rear main seal am I correct that the die cast parts in the slinger area are simply replaced by the die cast parts from later engines that can hold the rope seals?