I have a 1999 F150 in need of getting the maintenance caught up. 5.4L 70,000 miles, original owner. I plan on using our IRS stimulus payment to get the truck back into top shape so I can drive it for few more years.

Here's everything that has been done since I bought it:
1: Regular oil/filter changes
2: Transmission fluid changes
3: Air filters
4: Brake pads
5: Battery
6: Wiper blades
7: Tires
8: #4 ignition coil/plug
9: Added freon to A/C, suspect there is probably a small leak somewhere. I can live with topping it off every few years.
10: Replaced passenger's side door lock solenoid

Here's what I suspect needs to be done, any brand recommendations/installation tips would be helpful:
1: Spark plugs. Ford says they are good for 100K, but the truck idles a little rough (I notice it, DW doesn't) when cold. I think 9 years is long enough and it's something cheap to try before looking any deeper. With gas a $3.40/gallon I need the truck to burn as little of it as possible. Any brand recommendations and tips on pulling the back plugs would be helpful. I've had good experience with the Bosch Platinum +2 plugs on DW's Honda, not sure how good they work on F150's.
2: Shocks: Still has the originals, enough said..
3: Fuel filter: Never been changed, don't even know where it is.
4: Antifreeze: Still has the original, but looks clean.
5: Drivers side door lock solenoid is starting to go bad (sometimes need to cycle electric lock a few times to get ti to catch) Ford wants over $100 for the part, any place I can find it cheaper?

Here's what I think might need to be done:
1: Brake fluid, never changed when the pads were replaced. I'm not sure if it "goes bad".
2: Power steering fluid?
3: Rear differential fluid?
4: Serpentine belt, looks good but it's 9 years old.
5: Hoses: again, looks good but are 9 years old.

If there is anything I missed, let me know
I just realized I posted in the wrong section, not sure how to move it (or if I even can). Mods can you please move to maint section? Thanks

 

Spark plugs: OEM Motorcraft Platinums. These engines HATE Bosch. If you have already replaced one COP, buy a full set from Global on Ebay and change them all.
Definitely change the fuel filter, it's probably somewhere around the driver's door up behind the frame rail..
Time for a coolant flush.
Differential is good to 100k but if you do change it, it takes full synthetic 75W140, if you have limited slip it also needs a tube of friction modifier.
A detailed visual inspection of the serp belt will tell you if it's time yet. Same with the hoses.
I don't think a brake fluid or power steering flush is necessary.