I read up that if you want to remove the valve completely, the downpipe and cat have to come off to allow you to remove it.

I couldnt be asked with all that hag so just bought the stainless steel blanking plate from eBay, dropped the two 10mm bolts (I left a few turns on it), pushed the pipe down and slid it in. Took less than 10 minutes.

Peformance etc, the EGR operates iirc at low RPM. My focus feels more responsive and smoother with the blank in place, I've also added the ST170 airbox, snorkel and KandN filter which some say increase airflow significantly.