Flail Mower Help Reassembling my 951B bush hog.

[BJBHF]

Hi, I have a Ford 951b bush hog got it with property. I took old blades off put on spare sharper old blades. Went to put back together in order bolt blade though square hole then put on washer and nut. Tightened up with air gun only 90lbs pressure. One blade locked stiff couldn稚 spin by hand one blade sloppy seems bolt needs tightening more. To me a newbie it seems both are wrong. One too tight, one not enough. Is the washer in the right place and what am I getting wrong. Thx