Do you really just want Sheets 1 to 6 or to remove all code. If the latter:
This is an adaptation of code written and posted by Jim Rech:
Sub RemoveAllCodeFromCopy()
Const vbext_ct_StdModule As Long = 1
Const vbext_ct_ClassModule As Long = 2
Const vbext_ct_MSForm As Long = 3
Const vbext_ct_Document As Long = 100
Dim VBComp As Object, AllComp As Object, ThisProj As Object
Dim ThisRef As Object, WS As Worksheet, DLG As DialogSheet
Dim ThisBook As Workbook
On Error Resume Next
Kill "C:\Data1\Backup.xls"
On Error GoTo 0
ThisWorkbook.SaveCopyAs "C:\Data1\Backup.xls"
Set ThisBook = Workbooks.Open("C:\Data1\Backup.xls")
Set ThisProj = ThisBook.VBProject
Set AllComp = ThisProj.VBComponents
For Each VBComp In AllComp
With VBComp
Select Case .Type
Case vbext_ct_StdModule, vbext_ct_ClassModule, _
vbext_ct_MSForm
AllComp.Remove VBComp
Case vbext_ct_Document
.CodeModule.DeleteLines 1, _
.CodeModule.CountOfLines
End Select
End With
Next
For Each ThisRef In ThisProj.References
If Not ThisRef.BuiltIn Then _
ThisProj.References.Remove ThisRef
Next
Application.DisplayAlerts = False
For Each WS In Excel4MacroSheets
WS.Delete
Next
For Each DLG In DialogSheets
DLG.Delete
Next
End Sub