Hi Enticer,
Yes, you should fix that amp!
Having that 100W lamp in series to power up the amp without load is a good advice, follow it!
I would not do whole-scale electrolytic cap replacement, would only change the bad ones. Chances are the caps are just fine.
If the top of an electrolytic cap is bulging then it is bad, that needs to be replaced. Other than that you could check them in the circuit with an ESR-meter. You can build your own cheap ESR-meter, just google it!
This site has extensive info on audio circuits, check them out:
http://sound.whsites.net/articles.htmCheck the article section on
"Beginners' Luck - The beginners' Guide to ...", and especially the articles on "
Amplifier Troubleshooting and Repair Guide".
Good luck, Peter