Hi A17!
Admin CP => Styles and Templates => Template Manager => (Select 'Edit Templates' in the drop down menu for the template you wish to edit => Press [? ?] beside 'Postbit Templates' => [Customize] either 'postbit' or 'postbit_legacy.' Then just follow the instructions

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Anyhow, postbit is the horizontal one and postbit_legacy is the vertical view like the one you see here (notice how the data is all vertically oriented on the left column in this thread instead of horizontally).
If you need any more help don't hesitate to ask

. Oh yeah - the image is 21x21 for no reason at all

- it won't matter as it appears just fine

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