5.9l oil pan

I say if you are using the LA 360 pan, and LA front (timing cover, etc), then just use the LA 360 pan set. They work, and I've never had an issue with them leaking. Or else, try the one piece, make a video of what you did, and show us the results so we have a future reference. If it leaks, you'll just get to do it again, that's all :)