easiest way (honest) is to take the seat out and turn it over on a bench/table as you can spot the tell tale scrape marks easy then
after that a bit of brute force and ignorance is the key
most probably be the control bar for the forward/back release (reach) but i have known a couple with a break/split on the lower base frame itself - its easily stripped and welded up though just space/time consuming
*edit* DONT forget if you have side airbags to disconnect the battery for a while first or as usual if in doubt leave it to the experts