Level 29

You see a room which is 10x10m wide (0x0 to 9x9).
Every square has the exact temperature of 18°C. We apply continuously 173°C heat to the field 9x2
What is the temperature (rounded to whole numbers) in the field 6x8 after 43 iterations according to the Gauss-Seidel iteration

Field in the beginning

18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818
18181818181818181818

Field after 4 iterations (rounded after 4th iteration)

345666691823
47910101113255176
5911131314204195236
6101314151621366082
6101315161720273533
6111415161719212216
6101315161717171510
59121415151514116
479101111111084
2455666542

Temperature in field 6x8 after 43 iterations: