Blank Space Part 7

Logic

$\large 1 \, \square \, 2 \, \square \, 3 \, \square \, 4 \, \square \, 5 \, \square \, 6 \, \square \, 7 \, \square \, 8 = 9$

There are $2^7 =128$ ways in which we can fill the squares with $+, -$ .

How many ways would make the equation true?

Note: You are not allowed to use parenthesis.