as said by u the mid should be placed near the door opener I think it would be correct
and the tweeter can be mounted in three positions
1) flush mounted near the mid
2) there on the dash also ( can be viewed in the last pics)
3) side rearview mirror adjuster that can be a good place also (all the 3 componets will be perfectly in a same plane) ..
Navin ji where are u ........ Need ur comments on the same , and the 3-way also................