what kind of engine do you want to get? I always thought about a Chevy small block in my 96 Accord. Off the top of my head:

new engine, which includes mounting the engine in an engine bay that is probably way
too short, and still getting a radiator to fit. Would need a computer if you decided to not go with a carb.

transmission and fabbing up a transmission tunnel which involves modifying the body and putting the shifter someplace.

Would need to order a very custom driveshaft, since a regular one will not fit.

Need to get a rear end, possibly custom to get it to fit in the wheel wells and not stick out 6 inches from the body. Also includes figuring out somewhere to mount said rear end to, would probably need to figure something out with the suspension too.

Also would need various things like torque arm, new A arms, figure out how to mount the front tires since they dont have an axle and transmission holding them in place anymore.

Like I said, roughly what you would need, it can be done, I've seen videos of a RWD Ford Focus on the net before, and it would definitely turn heads to see a Honda Accord or Civic lighting up the rear tires, but I think it would be a details nightmare.