Thanks Paul. Yes, I definately will check currents before hand. You did mention earlier also about using the tpic6c595 high-current shift registers. In - built mosfets - excellent. Before I order anything, I'll run through the specs with you if that's ok.
Right now I'm just experimenting with multiplexing single LEDs, checking strobing and currents. I'm finding it just flickers at 50Hz, but stops at 60. So I assume 100Hz would be safe. I read somewhere that it should be 1000Hz
I've attached a sheet that I drew up earlier outlining how my 24V 7 segment displays are setup along with current draw, etc. From your notes above, I assume I will use tpic6b595's? I would assume then that I'd be using 2 of these per 4 digits. (ultimately I have 15 digits - timer, clock, home score, away score and temperature).