Statics Problem Help: Can't Get It Right - M=5860lb ft Off by 4

[Leece]

Please Help! I've been working on the problem for all day now and can't seem to get it right. One of my attempts came close to the answer in the back of the book but was off by about 4, the it should be at 30 degrees M=5860lb ft, and I got 5856. Along with this I have to enter the equations into an Excel spreadsheet, which isn't too happy with the equations I've found in the past. Any help or guidance would be much appreciated

 

[Simon Bridge]

Please show your best attempt.