A fused piece of 1.5mm pcb trace, warmed up laquer and then a clean
break, no smoke staining. I make that about 4 amps carrying capacity for
5 deg C rise along 25mm assuming 2oz board.
Anyway this is the main trace between earth bond point and common of the
secondaries and the speaker lines, all of which is 20 amp wiring.
Another 20A line from this bond point to the input pcb and no heavy
wires out from that pcb.
So 1/4 inch spade connections to the wiring off the ps board, but on the
board just this thin trace to the earth bond wire.
Just about goes with the "6 transistor" radio component placement and 2
fudged, topside only, rework replacement components, ie using the cut
stubs of the original leads to solder replacements to