Locating GPS coordinates in Exif tag

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Hi Simon.
I've tried to locate the GPS coordinates in an EXIF tag inside of a JPG file of mine.
I can use various tools to extract the data, but i'd like to write my own Excel VBA script that can process a directory of images and produce a KML file that I can open with Google Earth.

I've reviewed the spec at EXIF.ORG, but I fail to locate the actual GPS info in the file.

as far as I understand there is a TIFF header and then a GPS Info tag that points to the location of the GPS header. The GPS Header, in turn contains pointers to the actual location of the data in the file.

so first i need the GPS info tag. (This one I find as 2588 (little endian) rather than 8825 (big endian).
But from then on I'm stuck. I can't locate the GPS header at all. the offsets seems to be wrong. But the tools I've used (such as the ExifTool, Irfan view and Windows explorer properties) seems to locate the info without problems.

Can you let me know a simple process on stepping through the BYTES to finally locate the information I'm after?

I hope my question makes sense. BR/Patrick.Rehn@gmail.com