Alright, here is a snippet of code from the Display.Template.php file in one of the themes( an edit of SAF Multicolor)
// BEGIN SMFShop MOD New Version Code
echo 'Lüts: ', $message['member']['money'], '<br />
<a href="', $scripturl, '?action=shop;do=invother2;member=', $message['member']['username'], '">[Inventory]</a>
<a href="', $scripturl, '?action=shop;do=sendmoney;member=', $message['member']['username'], '">[Send Lüts]', '</a><br /><br />';
//END SMFShop code
All you should need is
echo 'Lüts: ', $message['member']['money'], '<br />
Change "Lüts" to whatever the credits on your forum are called. We have the section placed right after the karma section. I'm not sure if there's a way to add it without manually adding the code since I wasn't the one who did the SMF and SMFShop installation.
If it doesn't work, let me know.