ok, just realised, properties been set as Vf 1.66V, I 5mA by default in Multisim. Have to change them to 3.1V versus 12mA, simulate again.
From the graph attached I picked 3.2 V, 12.5mA. That gives 256 Ohm. Replaced the LEDs in the simulation with 75 x 256 Ohm and a 256 ohm in series. Legal? Then modified the other Rs so I end up with 3.11V and 12mA. Just relize, but it is RMS? But I am on the right track, just have to modify it for 2.26 V RMV across the diode?