Too Many Nested IF Statements -Another Solution?

I am using Excel 2010 and I thought you could have up to 64 levels of nested IFs statements vs. the previous Excel versions that only allowed 7. I would never nest that many but I have 8 statements that need nesting and I get rejected when I try to add the 8th. Not sure why since it should now allow 64 and my file is saved in the 2010 format.

Anyway -- can someone help me understand why 2010 is not accepting my 8th statement? OR if you review the formula - how I might approach this differently. Using Lookups, Match and other functions don't seem to lend themselves to what I am trying to do. I am trying to look at a series of cells on the same row and return the value from that series that meet the criteria. Here is the formula. It's the last If statement that causes the errror. Any suggestions are appeciated.

IF(ISERROR(Y2)," ",IF(Y2="Timing","Timing",IF(ISERROR(Z2)," ",IF(Z2="X","X",IF(AA2="NSF","NSF",IF(AA2="NSF Bank","NSF Bank",IF(ISERROR(AB2)," ",IF(AB2=I2,"Pr Mth Clrd",if(ac2="See Rec Item Sort","See Rec Item Sort,"")))))))))