Control three transistor switches from two pins?

Soo yeah. I've decided to not use some sort of transistor logic gate setup and go for a more tried and true approach.

Something like this:

Serial-in/parallel-out shift register 74HC164 into a buffer 74HC07 that will drive a N-channel PFET IRF511 which in turn switches my load on and off.

The load will look a lot like this:

And for my 12v supply I'll chain a max of three LEDs (Vf = 3v, Iled = 60mA) per 'loop' and calculate resistor for n LEDs with R = (12 - (3 * n)) / (n * 60mA).

You think I'm on the right track @DrAzzy? :) Here's the FET I've chosen for now: http://www.mouser.com/ds/2/308/EN8999-D-­256482.pdf
Vgs = 1.8V
Continous Current = 2A (will only ever see max 400mA)
Vds = 20V (need at least 12v)

EDIT:
I changed to using a constant current driver; http://www.mouser.com/ds/2/408/Toshiba_T­C62D723FNG_datasheet-340777.pdf
Much cheaper both BOM and construction time.