I've already checked.
They are all equal. Moreover the 1983 version missing half of schematic page.
To be more precise, in my physical pcb version R40 is missing and in their place there are two small little tantalum caps.
Moreover, I don't find any R43 and R44 on my pcb. The funny thing is that they are present on the schematic (1988 version) but not on the pcb layout of the same manual...
I'll try to ask Dave of Artekmedia if he has a suitable copy of the manual.