FWIW, after installing a few of these, most useful tip I can pass along:
These units come with a pre-cut pair of copper tubes bundled in an insulation sleeve that is sort of like a lamp zip cord insulation, and flared at the ends with compression fittings already installed. Pioneer/Highseer/PDHVac.com sells those copper pipe sets in 16/25/33/50 foot lengths. The interior units have two short copper pipe stubs, roughly 8-12 inches long, liquid and vapor, under the back side of the unit. Those two copper pipes are NOT the same length, presumably the offset helps keep two large compression fittings staggered to avoid quite such a large spot at one place. Before running the copper pipe set through the wall straighten it all out into one long piece, and work the right offset into the copper pipe set to match the offset of the interior unit. Then go ahead and run it through the wall or along whatever path. At the compressor end, you can coil, or cut the pipes at the exterior unit fairly easily as you'll have more working room around the exterior compressor. Easier to do it this way the fight the offset after you've run the pipe through the wall.