Evening all,
this might well be something that only interests me, but thought I'd share my findings as I've not seen it mentioned elsewhere.
If you want to have your own brand logos on the wrestler select screen you want to replace the ones in MnLayHD.pac / CHSM / 1B59
The 1B59 file was zlib compressed and when I extracted it. I didn't re-compress it again, rather updated (for non wrestler) the arc entry for the MnLayHD
...there was another useful image I found