Ordered 15 IV-6 VFD tubes for a next-gen retro calculator. Need a new display board, reuse old keyboard part and CPU. See https://github.com/eshazen/retro-25/tree/master/notes/VFD-Display Other observations. Looking at Japanese IV-6 breakout board and Eagle design from Osh Park, looks like 32 mil holes on a 0.3-0.34 diameter circle are good. Front-face is either between pins 8 and 9 or pin 9 depending on who you believe. Spacing is around 0.538 (13.7mm) (Japan). Data sheet says tubes are 13mm max diameter. Driver options: || '''Chip''' || '''Package''' || '''No Req'd''' || '''Notes''' || ''Price''' || || UDN2891A or UDN2892A || DIP || 12+ || Parallel 8 inputs || $3.95 (Jameco) || || MAX6920 || SOT || 8 || Serial interface 12 outputs || $4.82 (!DigiKey) || || HV518P || DIP40 || 3 || 32-output serial interface || $6.42 (!DigiKey) || || HV5812 || DIP28 || 5 || 20-output serial interface || $2.42 (!DigiKey) ||