Well I finally did it today. I was able to install with a lot of help from my friend, a 36 gallon tank on my 2011 4X4 ecoboost.
You only need 3 parts
1. 36 gallon fuel tank Part #9L3Z9002C
2. Heat shield Part#BL3Z9A032A
3. Extended Range Fuel Pump Assembly Part#Whoops forgot it at this time.
All other parts are interchangeable: the fuel lines, the filler neck, the straps, and skid plate. I made the mistake on buying more parts than I needed and I am now stuck with about $200 of unnecessary parts. Do not make the same mistake, just buy the 3 above parts.
Also note the fuel lines feel snug due to the different contour of the larger tank. This is okay, once the tank is in position the lines are fine and have slack in them. No need for a new filler neck, they are the same, they hook up at the same points on both tanks.
1, Put in park, block front wheels, jack up the rear, and use jack stands to support the rear of the vehicle.
2. use jack and support the tank, (best to have an almost empty tank) unbolt the front and rear straps, one bolt on each and bolts are located on the drivers side of the tank.
3. Unbolt the 4 bolts holding the drive shaft to the rear differential, lower the drive shaft out of the way to access the fittings on top of the tank.
4. Slowly lower the front of the tank, and then lower the rear while un-cliping the lines away from the tank (there are clips along the top of both tanks that hold the fuel lines for support). (white clips on top of tanks in pics).
5. Once all lines are un-clippped, and the tank is lowering first: disconnect the filler neck, then the green fitting next to filler neck, then lower tank more, then disconnect the fuel pump lines (warning: fuel will be pressurized and with come squriting out approximately a cup in volume) then disconnect the last green fitting at the front of the tank. So work backto front when disconnecting everything in order to spill as little fuel as possible.
6. Remove the fuel pump retainer ring and rubber O-ring, install these on the new tank with the new fuel pump. then remove the tab (little black mushroom thing) at the front holding the old heat shield in place. Use this piece on the new tank in the same location for the new heatshield.
7. New tank is ready to reinstall. Install tank while working backwards with all of the fittings. The fuel lines will be a little snugger on the top of the tank while out of position, once tank is Half-Way-bolted in secure the fuel lines by pushing them into the clips on top of the tank and check to see if they are tight or caught on something. Lines should have slight play in them.
8. once everything is connected, fully bolt the tank in, reconnect the driveshaft, fill with a few gallons of fuel, and cycle the key to ON (do not start the engine) for 30 seconds. Do this for 3 cycles. Vehicle should start up fine and allow to run in park for a few minutes to make sure there is no air in the fuel lines.
9. Head to the gas station and cry when you see your first bill.
I siphoned the fuel from my old tank to the new. I figured I had about 8 gallons left and ended up putting almost 28 gallons in. Not too bad for 2 and a half hours of work.
26 gallon tank is the one farther away in pics, 36 gallon is the closer tank.