Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 9°C. We apply continuously 142°C heat to the field 3x3
What is the temperature (rounded to whole numbers) in the field 3x8 after 86 iterations according to the Gauss-Seidel iteration

Field in the beginning

9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999
9999999999

Field after 4 iterations (rounded after 4th iteration)

1258865421
271830251711752
51847865733191173
830862299646251484
82557966539241594
61733463928191384
51119252419151184
471114151311963
2578988642
1234444321

Temperature in field 3x8 after 86 iterations: