6K tach mathces the one in this example (this site has the right image incidentally but the wrong redline figure). Bottom L78 tach is actually a 6K redline but they do look is deceiving)
Single fuel line.
Rear axle same week as trim tag (was told this is not uncommon on fisher tags from Willow Run) CBS 04 15 G 2 Carrier number 3968341
So I agree, looks L34 from bell housing back. Hard to convince myself someone would order it for high end and not stoplights.
www.chevynova.org/NovaTachs.html