Does anyone  keep a list of  parts for  recap power supply board [A18] on 2247A ?

I toke out the power supply  board [A18],  but can not find any diode mark as ZM or ZS which known to have issue and recommended to replace as well. 
All I can find is mark as Motorola instead,  diode issue not applicable to B290000 and later? 
My unit based on IC date code should be late in 1994.
It run fine but decided to recap before it fail, more than 20 years old  caps sound really scary.
However,  I found burn mark on my power board near area :- A18CR2228
A18R2255A18R2275A18R2254A18CR2227
Something went WRONG to my power supply board? FAN is running fine.

Could someone advise related to burn mark? should I worry? look scary to me

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