I have heard 12-18" from the turbo.
I would ask the Tuner who is going to be using the wideband for tuning where he wants you to stick it.
I just checked some old civic pictures, ours was about 9" from the V band at the turbo so that put it about 12" from the wheel.
203,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
Engine Build - Click Here