Ok, solved this - the top half is three arrow heads - the middle head is facing up whilst the two either side are facing down.
The middle arrow - the bottom is the "11" in row 18 - make this "11" central on that row. The tip of the arrow is the "1" in row 5, again make this central. Then make lines from the "11" in row 18 up to the "1" in row 5. There is then a small arrowhead within the bigger one, with the "3" in row 16 being the bottom and the "1"s in row 10 and 11 being the tip.
The arrowheads to either side has the "3"s in row 1, 2, 3 and 4 as the handle - the "3"s in row 1 starts at c2-4 and C22-24 - which should be the columns with the "5"s. The "8"s are then the bottom of the arrowheads in row 5 (first "8" starts in c1 and the last 8 ends in c25). The tip of the arrowheads is then in row 18 (the two "1"s) - the first "1" being in C3 and the other in C23. Again there is a smaller arrowhead within both on these, where the "3"s in row 7 make the bottom and the tips are "1"s in r12 and r13.