That grill block will net you your best MPG increase for mileage and also faster warmup times. I did a total block on mine also...........
I used black plastic truck mudflap material for mine and also incorporated LED markers and turn signals.......
I am still working on the headlamps..........
Your next best option is to install a block heater..........
I have mine on a timer for 15 minutes before leaving for work and I set it to 45 minutes on colder days. Good luck with your Metro project! You can read all the crap I did on mine here.......
http://ecomodder.com/forum/showthrea...ject-2936.html