Parts arrived early so was able to replace caps, diodes, and resistors above 1/4 watt.
Powered up yesterday afternoon and it came to life ... success!!!
Two other issues cropped up which should be minor:
Stereo light went dim and FM signal strength dropped to zero, light stays dim on other modes as well even though the actual mode lights illuminate correctly . If I cycle power the stereo light will illuminate as normal.
From reading an older thread with the same issue, it appears that replacing H801 & H802 (2SD331) brought resolution. Looking at the board one of the D331's was replaced with a D613.
Regarding the replacement, I've read conflicting part subs - MJE15030 vs. MJE15032G for the D331 ... which is more suitable in this application?
Second issue although now not really an issue was that when listening the audio in the left channel would drop out.
After pondering for a while, I inserted and removed a RCA cable into the left pre-out jack and the sound came back ..... jacks are dirty.
Having never heard this model before I have formed a very positive impression.
Lots of work still to be done, needs complete cleaning, replace a few missing screws (one shown in above photo), vellum, yada yada yada.
Focus is to get receiver operational, and once I get those two D331 subs in place I can clean this baby up.
Thanks to MBZ & Catrafter for your input.