Both the strainer and the sender use a 46 mm or 1 13/16" tool. The sender you can usually get a wrench onto the nut and turn it, the strainer you usually need a socket as there is no way to swing a wrench because of where it's located.

When pulling the strainer you should have a new replacement gasket handy or available. True Value hardware stores carry large O-rings that will work. The old one will be hard and might break as you remove it. It's hard enough to torque it back into place without having to reseat an old O-ring.

After running down the tank as much as possible drain as much as you can (the best way to accomplish that is to use a cheapo drill powered pump to suck the fuel from the fuel feed line in the engine compartment into a fuel can or use an extended section of hose attached to the fuel return at the secondary filter head and redirect the returning fuel into a fuel can, just pay attention that you stop the engine as soon as you see air entering the primary filter, you don't want to run the IP and fuel loop at the engine dry, that will just make starting the engine a problem once you get everything back together after dealing with the strainer issue). Then at the tank, under the car, above the axle, on the passenger side clamp the flex line with vice grips or something similar to prevent diesel from constantly dribbling out, remove the hose clamp that secures the flex hose to the steel line, separate the lines (be ready to have any remaining fuel in the steel line run out, have rags ready). Then you can peel back and disconnect the rubber boot that covers the opening in the underbody sheet metal that allows access to the strainer itself, loosen the boot and slide the boot down the flex line a couple inches, hold your thumb over the hose end, unclamp the vice grips that are below the now loose boot, and reclamp them above the lowered boot, catch the diesel that comes out of the hose when you remove your thumb with a rag. Then you need a 19 mm crowsfoot to remove the flex line's fitting from the strainer. Sometimes the entire strainer will uncrew as you try to remove the flex line fitting, if it does great. Have a couple containers ready to catch the diesel that will come out, make sure they are close at hand and that they will fit under the car! Could be a quart of diesel could be a couple gallons! Be ready for either.

With the flex line removed you can get the 46 mm socket onto the strainer, you'll need a couple reducers (a socket that large is usually 3/4" drive at least) and a couple extentions to reach up to the strainer, and a large ratchet or a breaker bar. It can be a challenge to hold the socket on the strainer and apply torque to the breaker bar, you want the breaker bar below the axle so you can get the swing you need and a good pull. Break the strainer free and then you can unscrew it by hand usually, be prepared for more diesel to drain down when you finally remove the strainer. Have a couple rags ready so that once the diesel stops draining you can stick a rag or two up into the space that is between the fuel tank and the steel underbody, it's maybe 1/2", because a little bit of diesel will drip out of the opening and sometimes rather than falling straight down it will run off to the side a bit. If that happens it will get into the space between the tank and the chassis and your trunk will smell like diesel for a long time afterwards.

Clean the strainer with gasoline or carb cleaner, if there is obvious scum in the tank, you can get a couple gallons of fuel and pour it into the tank from the filler and hopefully flush much of it out that way, use a couple buckets and a funnel underneath. Then once you pour the fuel through, let it settle, then pour the clear clean fuel on the top back through again until you don't have scum particles coming out any more.

Assemble the strainer with a new O-ring, lightly oil the O-ring so it doesn't stick and deform out of position as you retorque it into place. If your flex line is intact you can reuse it, or you can replace it, or you can cut the old hose off the fitting and attach a new section of hose to the bibb on the fitting and secure it at that end with a hose clamp. Put the rubber boot over the line and manuver it into position with its edges secured over the opening's surrounding lip, make sure it's in place and not twisted, its purpose is to seal the chassis opening from water and grime getting into the trunk/tank area. Reattach the flex line to the steel line with a hose clamp and the job is done. You can then grab your bottle of Dawn and hit the shower to stop the diesel fuel burning in your armpits!

The sender can be carefully disassembled and then you can soak the bottom section in gasoline to disolve any sediment/slime that has accumulated inside it over the years. Be careful of the wires, better to not touch them just use soaking or maybe a spray can of carb cleaner. If you have a hesitant reading fuel gage or a funky reserve light function cleaning the sender will usually correct those things.