[TYPO3] how do i limit a plugin to a usergroup using typoscript?

[dave typo]

for example, I have

lib.topMenu <  plugin.tx_dkdfeuserbelogin_pi

but I can't find the typoscript under the ts ref.

i assume its something like

plugin.tx_dkdfeuserbelogin_pi1.usergroup = 8

or something.. anyone got the answer?

thanks

-dave