If its got aircon then the white box behind the glove box is the air con stuff, the matrix is behind the centre of the dash.
I did mine last year it involved "FULL" removal of the dashboard and a lot of wiggling and swearing.. and I was on it all day ! (some bolts and screws are a b*stard to find)
I got one from TCB for ?70 second hand delivered to my door ! Toyota wanted approx ?250 + VAT for a new one !!! you can get them repaired by a radiator company but the costs and time scales can vary !
Best of luck with the job. If you've got any other questions shout away !
Chipster [ICOC]
ST183 4-WS (Auto) 1991