[Hunts smoothing bomb]

This is interesting as there are no apparent short circuits on the HT rail, you have proved this by testing across C702.

It is hard to tell looking at the pic but is there a hair line crack in C703?

Replace these Rifa capacitprs anyway as even if they are good now, they are likely to cause trouble in the future.

The fuse does not look like it blew violently as there is no sputtering or blackening of the internal glass wall, I am puzzled where the smell came from though, it looks (at the moment) as though the fuse has failed under natural fatigue. Is it possible that the smell was not related to a fault maybe and is indeed a red herring?

Have you tried inserting a new fuse and disconnecting C703 and powering up?

Cheers