If Albert is happy for me to share i will post them up. the files were the originals converted from x1 to 274x with a little tidying up, hench the mistake on the pcb. it is fixed now on the gerbers.

Go ahead - post away!  I can also put up an easy-to-build 15 kHz LPF pair to replace the unobtanium Toko filter.  I'll sort out the notes and post shortly.