Sumproduct across multiple worksheets (3d search)

[lindstroem]

Hi,
I have been using a SUMPRODUCT(SUMIF)-based function with INDIRECT function pointing to a table with named sheets to sum up information across multiple sheets.
Example =(SUMPRODUCT(SUMIF(INDIRECT("'"&Projectlist&"'!BK4:BK16");R5!;INDIRECT("'"&Projectlist&"'!BO4:BO16"))))

I now wish to expand this to have the SUMPRODUCT functionality in the sheets as well, rather than the 2d-SUMIF. I wish to have 2 vertical search critieras and 1 horizontal, I tried using a SUMPRODCT(SUMPRODUCT)-but that didnt work very well. This was my attempt:

=(SUMPRODUCT(SUMPRODUCT((INDIRECT("'"&Projectlist&"!B4:B53")=R5)*(INDIRECT("'"&Projectlist&"'!A4:A53")="Hours")*(INDIRECT("'"&Projectlist&"'!H2:T2")=S3)*(INDIRECT("'"&Projectlist&"'!H4:T52")))))

Basically vertical search criteras R5 & "Hours", and vertical search criteras S3.

Perhaps that approach is a bit to blunt, anyone have any ideas hon how to get this functionality?