Chassis vibration after clutch replacement...

[16g Spoolin TSi]

So the clutch i decided to go with on my 99 GSX was the ACT 2100, i got my flywheel machined while i did the clutch, the flywheel looked awesome when i got it back, never really looked bad to begin with... anyways everything got put back together monday afternoon and since then i've put on about 50 miles... heres my question- on downshifts more noticable 3-2 i get this real noticable chassis vibration, nothing in the pedal at all. Is this just the clutch breaking in seating itself on the flywheel or is it something else, something bad I'm real anal about stuff like this with my cars bc the car drove so smoothly before so if anyone has any info please i really need it
thanks
~Johnny

 

[Defiant]

Make sure your bell housing bolts are tight.