[TYPO3] Select pro and contUid

[Piotr Burda]

Hi

I`m trying to adapt SelectPro to my site, i`ve learned how to put GET 
variables into the query, how to generate contUid, but...
the extension generate link to detail page like this:

index.php?id=1802&contUid=816

on this page i` have my own extension who needs the link:

index.php?id=1802&tx_pbtestext_pi1[showUid]=816

The question is how to pass variable value from contUid to
tx_pbtestext_pi1[showUid]


Regards

Piotr