I havent seen this kit other than pictures. But it seems that it is an iso-mount kit... meaning the trim ring around the radio is not used/and or will not fit.

I have a Pioneer 8400 head unit and this unit looks fugly without the trim ring...

Will the trim ring fit on the metra dash kit.??

 

The Metra Kit is either ISO mount, or DIN mount....you choose how you install it.

So, yes the trim ring should fit.