Any tricks to make it easier?
The old trick of using a length of fuel hose as a starter always comes in handy when dealing w/hard to reach plug locations- the hose acts as a big universal and allows the plug to be turned from "around a corner" if need be.
It always helps to have an assortment of plug sockets and socket/extensions for getting into various spots as the need arises.
3rd. from the left is a locking extension. Nothing better than having a plug socket w/a nice, tight sleeve inside for holding that plug while you search around blindly for the hole. But nothing's worse than losing that same socket, plug and all, because the sleeve had a better grip on the plug than the extension did on the socket!
The locking extension- or the "one piece" socket and extension (bottom) does away w/all that mess.
The other various tools (swivel sockets and wobble extension, etc.) are what you'd expect to find in most boxes. The extra-long socket (far left) is actually handier than one might think at first. It does away w/the need for an extension in many cases and gives a good purchase for turning.
Don't forget the hex on the plug sockets are there to aid in cases where a wrench may be able to turn the socket when a ratchet can't. Especially a stubby Gear Wrench

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DoubleVision said:
The corrosion from the A/C`s use seized the lines on.
Obviously, using a wrench on both sides of the union will reduce the chance of damaging the tubing or fittings- where this can be done. Flare wrenches are always a good idea- necessary even- when dealing w/aluminum tube/fittings.
Somewhere around here, I have a couple adjustable wrenches with 3/16" thick steel "flats" welded onto the jaws for just such a thing. The ~1/4" wider (on each side of the jaws) flats spread the load on the
big fittings better than a regular adjustable, open end or flare wrench, all of which are very narrow for the width of those larger AC fittings.
A little too late to help your bro' in law, though

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