[MrFixr55]

Hi Glen,

My stab in the dark is to:

• Measure the full secondary resistance.
  
• Measure from the leg that is grounded to the feedback tap.
  
• Divide this resistance by the full resistance to get a ratio of tap resistance/full resistance.  These resistance 
  
• values will be quite low but hopefully the meter sensitivity and resolution is good enough to give you an
  
• accurate ratio.
  
• Duplicate the ratio with two 1 Watt resistors with the larger one being 100 Ohms.  Put the 2 resistors in series   
  

         with each other and this pair of resistors in parallel, with the output transformer, with the "leg" of the lower resistance value on the
         grounded end of the transformer and the leg of the higher resistance value to the other connection to the loudspeaker.  The junction of 
         the 2 resistors is the feedback tap.

Hope this helps.