A basic set up (assuming headers in row 1) is:

**Column A** = Raw Data (e.g. -116.6412722 34.7459017)

**Column B** = Raw Long `=VALUE(LEFT(A2,FIND(" ",A2)-1))`

This will split the raw data into just Long, and treat it as a number, rather than text.

**Column C** = Raw Lat `=VALUE(RIGHT(A2,LEN(A2)-FIND(" ",A2)))`

This will split the raw data into just Lat, and treat it as a number, rather than text.

**Column D** = Converted Long in DMS `=IF(B2<0,"W","E")&TEXT(ABS((TRUNC(B2,0))),"0")&"."&TEXT((ABS(TRUNC((B2-TRUNC(B2,0))*60,0))),"0")&"."&TEXT((ABS(((B2-(TRUNC(B2,0)))*60)-TRUNC(((B2-(TRUNC(B2,0)))*60),0))*60),"0.0000")`

**Column E** = Converted Lat in DMS `=IF(C2<0,"S","N")&TEXT(ABS((TRUNC(C2,0))),"0")&"."&TEXT((ABS(TRUNC((C2-TRUNC(C2,0))*60,0))),"0")&"."&TEXT((ABS(((C2-(TRUNC(C2,0)))*60)-TRUNC(((C2-(TRUNC(C2,0)))*60),0))*60),"0.0000")`

Then, fill down as necessary.

You can do this with varying numbers of helper columns, if you want to troubleshoot possible errors at each step. Also, your sample data seemed to calculate differently, so I'm not sure where your numbers were coming from.