QUOTE(jaredmcginness @ Dec 3 2020, 12:20 PM)
These were used in Longhood 911/912, 3 and 5 gauge consol, up to '69.
More specifically a 6k redline is a 912. so 66-69.
914 '70+ has always been red needle VDO.
GLWS
Edit: It is also date stamped January '66.
Basically correct. This is a 912 part. The red line tells the tale. Also important to note it is a 4 cylinder tach, so not just the red line is different than a 911.
The 912 and 911 used this type of gauge from inception in 1965 through 1967. In 1968 they went to a white letter format like we see today. What differentiates those from 1970 and later tachs is the standoffs in the back for mounting. These cars used a bracket that attached to the back of the gauge, rather than press fit rubber seals.
There are cases where folks installing a 912 engine into their 356 may be interested also. The 356 used a mechanical tachometer drive which ran off a gear on the oil pump cover. If they convert to a 912 engine, and elect to not transfer the oil pump gears and cover from their original engine, they would need this part also.
GLWS, hope this background helps guide you.
There is a place to try and sell this at 912bbs.org. You can also try the for sale section on Pelican Parts, though it may be less traveled.