EG6's came in auto....?

Anyway, you will need modification, definitely.

For starters you should search this on google as I'm SURE B16a into EG has been covered 100 times here and on different forums. I also know for certain there is a complete DIY on swapping a B series into civic/crx in the DIY section of this website.

You will need the B series engine mounts from your EG6, you will need the driveshafts and exhaust too.

You will need to add a few wires for VTEC and knock sensor, and pins for the ecu plug.

There's more to it, but go check out a DIY/write up.