Anyone? - TLC5940, 16xRGB LED's Plex on High Side, PWM on Low?

Has anyone tried plexing 16 RGB's (high side) whilst PWM on Low side through A TLC5940 and ULN2803A
darlington array?

Would appreciate any feedback on the suggested approach, attached a simple schematic of what I'd like to do
on the electronics side, software side I appreciate may bring its own challenges! :smiley:

Note, each channel will have an array of 3 RGB LED's and will be driven from 12v supply

TIA
Monty