Subaru Upper Turbo Heatshield Removal

It may be worth spraying down the bolts with a penetrating oil and allowing them to sit for a little while in order to allow them to come lose more easily without any breakage.

Using your 10mm socket remove the two bolts from the driver's side of the heat shield.
Followed down by the one on the rear passenger's side.
And the two low down near to the passenger's side frame rail.
With those items removed you can now remove the heatshield from the car.

It may require re-clocking the transmission dipstick in order to have the clearance needed to remove the heatshield easily.
Now is a good time to check out the heat shield bracket as the factory units are quite prone to cracking and damage. Replace yours as needed.