Incrementing Range Programmatically

I have the following function that looks at a range of data and deletes duplicate entries in each column. I want to change the range that is examined programmatically, rather than having to retype it for each range in this huge sheet! I have subtotaled and counted the rows in each range, so I know how many there are, but I'm stumped as to how to increment teh range correctly. I'm attaching a small sample of my data. The full sheet is 30,000+ rows and 94 columns.

Sub DelDups2()
Dim rngSrc As Range
Dim NumRows As Integer
Dim NumCols As Integer
Dim ThisRow As Integer
Dim ThatRow As Integer
Dim ThisCol As Integer
Dim J As Integer, K As Integer, x As Integer
Set rngSrc = ActiveSheet.Range("c68", "cr70")
NumCols = 94
NumRows = rngSrc.Rows.Count
ThisRow = rngSrc.Row
ThatRow = ThisRow + NumRows - 1
ThisCol = rngSrc.Column
For x = 1 To NumCols
For J = ThisRow To (ThatRow - 1)
If Cells(J, ThisCol) > "" Then................