Syntax For Referencing Other Workbooks / Worksheets

I'm trying to optimize code by avoiding activating other worksheets, but I'm running into a problem with a match function.

I'm using a workbook called "Template" and then opening another workbook called "DCP" and trying to use the match function to figure out what row data is on. I can get this first line of code to work:

HTML Code:
MatchedRowNumber = WorksheetFunction.Match(Combo, Sheets("Sheet1").Range("A:A"), 0)

However for that to work, I have to activate the other workbook. I want to avoid that and stay within the "Template" workbook. I think I need something like this:

HTML Code:
MatchedRowNumber = WorksheetFunction.Match(Combo, DCP.Sheets(DCPSheet).Range("A:A"), 0)

That one however doesn't work... looks like I have the wrong syntax.

Below is an excerpt for the code in case something is wrong with how I set the variables.

HTML Code:
Sub StockOrderByDCP()

Dim Template As Workbook
Dim DCP As Workbook

Dim MSS As Worksheet
Dim DCPSheet As Worksheet

[Code] ..........