[Gprename-users] backreferences ?

[Hippo31 <hi...@fr...>]

Hello,
I recently discorered this nice tool and feel it quite useful, but i 
would like to make a replacement like this "s!- (\d+)!\1 -!"
Through gprename i have tried
Replace "- (\d+)" with "\1 -"
and also
Replace "- (\d+)" with "$1 -"

but the displayed result doesn't look like what i was expected

Isn't there possible to use the backreferences in the target space ?

Hippo31