Power transistors blowing fuses

My 40yr old vintage Sansui A80 integrated amplifier has now started blowing fuses. Nothing looks visibly amiss - no cooked components or leaky capacitors. But 40 years takes its time on any piece of electronics. It has had a good innings and a huge amount of use, so recycling for a new one seems in order.

However, replacement components are available. I have now extracted the offending power capacitors (2 of 4) which showed dubious readings in-circuit. Isolated, they show open circuit across the collectors and emitters. With luck it is just the dried out heatsink compound that has brought on their demise. If it is more serious and other compoenents are faulty, then I suspect it may just be a hiding to nothing, but so far - I have spotted nothing else. 

New parts on order, so if they work I will consider replacing some of the ageing capacitors to give the old amp a bit more life.