It makes no difference whatsoever.
That's what I'd do, assuming I understand you correctly. Two strings, each comprising four LED's and one resistor in series. Fed from 12V.* 2 series of 4 LEDs in parallel with a 120 ohm resistor at 1/4w on each series.
120R will give you 16.6mA which ought to be fine. 100R will give 20mA.