change keyboard layout in OS X 10.5. 500 points.

hi experts

i've just been given a MacBook at work, running Mac OS X 10.5.5. i ran the set up, and selected my keyboard and language (both British/English/United Kingdom, can't remember which now, but all the same for this).

problem is, as a PC user, i really want the "@" symbol to be under the "'" (single quote/double quote) key, and the """ (double quote) symbol to be under the "2" key. also really want the "#" symbol under the "\" key. basically, i want a PC layout for the keyboard.

is there any way i can do this? i've tried the obvious, like trying to change it under "System Preferences > Keyboard & Mouse" and "System Preferences > International" but it won't work. also tried running set up again by running:

sudo /System/Library/CoreServices/Setup Assistant.app\
/Contents/MacOS/Setup Assistant

but that didn't work either.

any suggestions?

thanks