Hi, Dan
I did something similar to scroll to a particular row in the Keyboard pref pane's text substitutions - effectively:
set matchedRow to (row 1 ...)
-- Select the row, then move the cursor up and back down to scroll to it
select matchedRow
key code 126
key code 125
Jiggling the cursor keys seems a bit lame ... but it worked! (You may need to swap the order to down then up for the first row, I guess). I'd be interested to know if there was a better way 
Best wishes,
Steve