[R-390] Smoke got out

[dog]

So I'm about to sell this guy this 390A and I turn it on and notice that 
after 5 minutes or so the noise level of the RX goes way up. Figuring 
it's a tube problem, I start swapping tubes out. I get to the RF section 
and turn the radio on and all of a sudden I see a wire in the harness to 
P108 melting in real time and smoke starts coming out of the RF section 
over by the crystal osc. Turn off the power and unplug it. Well, it 
appears as if the wire to P108-B has burned up. That's the 6.3V for the 
filaments in the RF, Crystal osc, the break in relay, and the filaments 
in the audio section. So it looks like I've got my work cut out for me. 
Better it happens now than right after the guy gets it home after a 4 
hour trip. I'll dig into it today, it's going to be a challenge to 
replace the burned wire/wires in the harness. Think I've got some Teflon 
wire I can use to replace it. Wonder if it's one of the tubes that's 
shorted?