quite interesting... i did part of this mod in the past, just swapped the running lights and signals, as per 1-5 in the instructions here. i wanted to somehow change the main (brake) bulb for a dual-filament that could work as running/brake light, but could not find a suitable holder...
is Chevy Metro same as Geo Metro?
also, i found that the rear-light lense dispersed the light too much, so with for ex. right signal flashing, the whole lens light up, , and standing on the left side, it looked like the left signal is on...though from the back you could tell that the right side is a lot brighter.
did you find this to be a problem? Is it less of a problem with LED globes? i'll have to give it a try.
thanks for sharing, this is great stuff!