highlight match's without conditional formatting?

Hi

I have a report in Excel 2003, where i enter lots of numbers which i need to higlight if a match is found.

Basically, i enter the numbers in the following columns:

J,K,L,M,N,O - From rows 7 - 200
AE,AF,AG,AH,AI,AJ - From rows 7 - 200
AZ,BA,BB,BC,BD,BE - From rows 7 - 200
BU,BV,BW,BX,BY,BZ - From rows 7 - 200
CP,CQ,CR,CS,CT,CU - From rows 7 - 200

and I need to know if a match is found in any of the below Columns

DD - From Rows 3 - 1000 (Range Named Orange - Highlights in Orange)
DE - From Rows 3 - 1000 (Range Named Green - Higlights In Green)
DF throught to EZ - From Rows 3-5000 (Range Named Blue - Highlights In Blue)

I can get this to work with a conditional format, however due to there being so many numbers it has to check against, it kills the performance of the report, so far that it becomes unusable.

Is there anyway i can get around this to make it faster and not make the file size huge (either through a macro or conditional formatting)?

Any help would be much appreciated.

Edit

Oh and just to confirm, the numbers need to highlight in the section below

J,K,L,M,N,O - From rows 7 - 200
AE,AF,AG,AH,AI,AJ - From rows 7 - 200
AZ,BA,BB,BC,BD,BE - From rows 7 - 200
BU,BV,BW,BX,BY,BZ - From rows 7 - 200
CP,CQ,CR,CS,CT,CU - From rows 7 - 200

anyone? please?