As far as I know, a B16 (2000 Civic SI engine, for example) with a mount kit and some slight fabrication will fit pretty nicely...

what makes it harder is you'll be switching over to fuel injection... you'll need the gas tank, lines, pump and all sorts of other nessecities from a LX-I.

I wish you luck, as its definatly different... If you need any stock parts for the car, let me know, I have a parts car here.