how to add custom timings with ccc 6.2

i have a my 65 inch hdtv connected as my secondary via component out off my
aiw9800

hdtv at the 1776 x 1000 is almost perfect. for 720 p programs pristine

for 1080i just a little black horizontally at the bottom that needs to be
pulled down a tad
how can i tweak the 1776 x 1000 setting to lets say 1800 x 1000 or play
around with numbers till i get it right.

i have ccc 6.2 but cant seem to find a screen i remember in a previous
version of ccc that let you enter specifil numbers for horiz and vertical
resoltion.

tia

jeff