[Arran]

Arran,

I would understand if those #61 and 62 smoked, things being the way you explain. This would take a lot, as the resistors are probably 2-3 watters at least, and the voltage without load, I take it, about 400V or so, and so between the two of them they will dissipate 2W, which is far from making them smoke.

But #7 smoking.....removing the field coil actually removes the power from just about anything, except from res. #22 / 21, which is hi-resistance, and DC-wise foes to one of the Det.osc. grids, so there is no DC path.
No current flows anywhere anymore.
How does that makes #7 smoke, I fail to see, unless, there is some short somewhere, or something else.

A long shot - shorts within coils and within the tuning capacitor may do it, but if this is true, then this would be a good day to go and buy a lottery ticket.

The schematic and parts list does not give a wattage value on resistors #61 and #62, it also does not mention whether they are wire wound as it does with some other so we would have to assume that they are both carbon composition resistors. From the under chassis parts layout diagram you can see that resistor #61 looks like it may be a 2 Watt but #62 is no more then a 1/2 Watt judging by the physical size shown. In those days it would be rare to find a carbon resistor over two watts anyhow, especially in a circuit that would not normally be dissipating up to 450 volts should the field coil be installed.
As for the part #7 resistor there are two ways that I could see a potential B+ path to ground. The first would be a grid to cathode short in the 6A7 tube, although you would need two grids to short together and to the cathode which seems unlikely. The second way would be for part #19, the .0001 uf capacitor to short out, this seems more likely especially if it's a paper capacitor, not common for a mica to do this but not unheard in a radio this old either. The spike in B+ voltage may hve punched a hole through the dielectric of #19 capacitor, this is assuming that there were no wiring errors and that there wasn't anything causing a short by accident like a lead bumped over or a blob of solder falling in the wrong place like between two pins on the tube socket.
Regards
Arran