The Lat/Lon fields in your excel sheet will need a lot of cleaning.
Apart from the quotes, you also need to remove rows containing other string values (e.g. Parking Lot and other Text values) or you can replace the text with the numeric Lat./Lon. values, if you know them.
For deleting the quotes MS Excel, select all the cells of Lat./Lon. columns. Then execute a Find and Replace (Ctrl + F). Replace " with blank (Don't put any space). Click Replace All.
Also replace other texts in Lat./Lon. columns with their respective numeric Lat./Lon. values.
Think Location