Make and model make a difference too, and what part of the 1980s? Remember, there were recessions then, two in fact, and many manufacturers cut corners to stay in business. The brand of the cap is important....quality is quality, the bottom line.
You do not state if this is tube or solid state, that makes a difference. Yes, bring it up slowly to 1/3, then 2/3, then full is a proper way, but not necessarily if it is transistor.
My suggestion is replace the fuse with 1/2 amp rating, speakers attached, no input. If transistor bring up over 15 to 20 minutes to power, if the fuse pops, then the caps may have shorted. If tube, bring up over a longer period, may be 3 to 4 hours.