Well you need to rethink what is happening with only those 2 files man.
If it says please insert service pack to you have either done one of two things
You deleted the .tst for sp2 from the root of the file and you forgot to update your txtsetup.sif in the setup directory not the i386.
Or you kept the .tst for sp2 in the root of the folder...but again forgot to update your txtsetup.sif file so now your not actually installing sp3 yoru installing sp2.
now if you deleted the sp2.txt from the i386 directory but kept it in the setup directory (like wpro...not uneglishwpro just incase your confused on that) you are still installing sp2.
this can go many ways here...but i think you see that you have to update your sp2.tst in the root of the directory to sp3.txt (that\'s not the real name i forget so i call them sp.tst) and the txtsetup.sif in the stup dir (wpro) to have it work right.
Your patch can work too but as we all know to patch something is not a clean way, but in ways, dirty.
Now you can\'t as far as i know, get tricky with it and keep all 3 sp\'s like that. I think some files do no matter what get updated no matter if they are in the sp3.cab or not.
But if you wanted you could try to copy 3 setup dir\'s for each 2k and see if it works. I think it just would act like it is install sp1 but really copy over files from the sp3 alos...or might not work at all.