Your best bet is to scarf the plywood to full length and then cut the panels. As best as I can figure, there's 2 benefits to doing this

1. You don't have to fudge the measurements by adding 5/4 inch here or there

2. You eliminate the possibility that you won't glue the panels together completely straight.

3. (Just thought of an extra) While you can still cut both panels at the same time if you scarf after you cut the panels, you can cut full length panels at the same time if you scarf before you cut the panels.

Lastly, it's pretty impressive to look at a 16'x4' piece of plywood if you've got the space.

As always, this is far from gospel. I've no doubt that someone else will say to do it the other way, and they'll be just as right as me (Probably more so). I scarfed and then cut, and am happy with how it worked out. Try it either way, and let the board know how it goes.

Bill Jankowski