My goal: become another one of the Metros/Swifts to be registering in the 60+ mpg realm.
DONE (at least, a couple of times) I want to start doing things that will make a difference, as I can. But my budget's about gone for awhile, so I need to start with the free/cheap stuff. This is my first attempt to "list" them, more-or-less in order:
1) Air up the tires to? 155-80/13 Can they handle 60, I wonder?
DONE - keeping them at 60
2) Front grille block with black duct tape - nicer one later
DONE - nice enough - maybe no need for a "nicer" one
3) Fuel injector kill switch for better EOC-ing
4) Hand throttle control, so I can drive long distances easier
5) Rear wheel/4-wheel alignment. Outsides of rear tires are wearing badly
DONE
6) Engine/oil pan heater. Not super-cheap, but it's winter & I want MPGs!
7) Rear fender skirts - cardboard first for A-B-A testing, then nicer - maybe
DONE - coroplast. not sure if they do anything, though
8) Full belly pan
9) Front & maybe rear wheel covers and/or fairings/spats
10) Kamm-back/partial boattail
11) At some point by about now, I'll need new tires - will try to find LRR
DONE - but not LRR. Couldn't find in 155-80/13
12) When the next oil change is due, go to Mobil-1, 0w20
DONE - sort of. Mobil-1, 0w30 all summer, but about to change oil again and already have the 0w20 
Suggestions? Should I change the order of this list? Some things found to be "not really worth it" by other Metro/Swift owners?
Thanks
PS: In looking through the list, it looks like there are no FOUR cylinder Metros/Swifts in the top of the MPG ratings..... Looks like I've got my challenge - gotta change that!!!!