split screen

I am doing a projection piece for a gallery and need to do a split screen piece.
I have worked with split screen many times by scaling the videos down in the Motion tab. The resulting videos don't fill up the frame. The gallery wants the two videos to fill most of the screen. Someone suggested I crop in FCP.
I am working with a Panasonic DVX100 and FCP 5.4.
What is the best way to shoot? If I crop, don't I have to make a template for the camera so I know what will be in the shot? I do a lot of close-ups so this will be difficult.
Should I shoot in 4:3 or squeeze mode (the DVX 16:9 )

So...in one of my previous split screen pieces..the each video is 5"H x 7 1/4" Won my 22" wide screen TV. (in 4: 3mode) In a commercial film with split screen each video is 7 1/4" H x 9 1/4 W.(in full mode)
How do I get my videos to be as large?
Thanks,
Eileen

Hmm. If you're showing across two 4x3 monitors, the resulting image would have an aspect ratio of 8x3, or 24x9. That's 2.66:1, which isn't all that far off from 2.4:1. Does your camera have a 2.4:1 aspect ratio guide option for the EVF? I want to call that a ground glass, but I doubt that's what your manual would call it.

If you shoot 16x9 with 2.4:1-safe, you'll be able to blow the resulting footage up to the proper aspect ratio with only a little cropping on the bottom and top. I think that'd probably be the best bet for shooting it.

As for exactly how you'd edit that piece, I'm afraid I don't have any good suggestions. I've never done that kind of job before. Maybe you could set your raster to 1440x480 in Final Cut and do your work there? You won't be able to work in real time, I don't imagine. And outputting your masters is going to be a pain, if you have to deliver two separate tapes or discs or whatever, one for the left screen and one for the right screen.

Hi
I am not using two monitors. I am projecting the piece. But when I do the split screen my way it is too small.
So..any more thoughts?
Eileen