Low cost, high performance headphone amp using OPA1656 and LMH6321

The spice schematics show the CL resistor as 18k fed from the +15V rail. The notes on the schematics say that the 18k resistor sets the current Limit to 270mA per channel. However, according to the LMH6321 datasheet the programing current limit is 15V/18k=833uA programming current which would result in 400*833.33 uA = 333.33mA output current which is more than the maximum specified. I thought that the 270mA was lower than necessary to drive LO-Z headphones, but the correct resistor value is 20K0 -- not 18K when fed from +15V. 15/20k=750uA which is the maximum programming current and gives the maximum safe 300mA output from the LMH6321.
 
Only now I am catching up with populating the board from the original batch.
The links in post 74 (Mouser) and post 78 (bom) do not work anymore.
Assuming no update on the parts list have emerged up to now, can someone please re-post?

Furthermore, Wyn mentioned an add-on board in post 84. Would you please share a schematic?