clutch arm

[skyhighatv]

just wondering if anybody knows the rough lengh of a blaster clutch arm-im building a motor in a box my buddy got and the clutch arm wont drop all the way in-you can see marks from the needle bearing on the arm about 1 inch from the bottom of the arm-so it looks like it was used in this motor before-i just need to know if its the right one!
thanks