@YYCHobbyMachinist : make sure you clean off all the old liquid gasket and then use acetone or some other non residue cleaner to be sure both plates are oil free. Apply a thin amount of the sealant as you do not want it gumming up your gears - once you re-assemble let it fully cure before you add oil. I cannot recall any gasket or sealant on the donor lathe. If the apron piece is still in the junk bin I will see if there is any tell tail signs.
There is no mention of shaft seals in the parts list, and either @YotaBota or @Hruul (one or the either or both) confirmed not finding any as well.