Samurai 8-grid Calcudoku puzzle

Here’s probably the largest Calcudoku puzzle you’ve ever seen!  It’s made up of 8 underlying 9×9 grids, each of which must have 1 to 9 placed into each row and column, and then on top of this I’ve added the familiar Calcudoku regions.

For each Calcudoku region just place numbers such that the total after applying the stated operation between the numbers in the region is the one given.  For example, 7+ could be solved by 3 and 4 (3+4). For subtraction and division start with the largest number in the region, so 1- could also be solved with 3 and 4 (4-3).

Just to make it really clear, there are no 3×3 Sudoku box regions in this puzzle – just the 8 sets of rows and columns.

Good luck! :)