Hahahaha okay this is wack.
The poster wants fuel economy AND power at the same time, and you guys are suggesting Turbocharging a D-series, swapping in a H22, K20, B16? Pathetic.
@poster: With all due respect, since it's Papa's money, let me ask you, are you facing any problem with your current engine? If not, then swapping in a D16Z6 would be a waste which is the best option here in terms of fuel economy and a reasonable amount of power for a daily runner.
Oh and PLEASE don't rice up the car with "Kick-**** "visual mods".
Stock is best with just a few upgrades here and there.
Reply me with an answer and I'll guide you further with this, peace 
and not to forget, I will quote Ahad's signature here:
Reliable, Fast, Cheap....Pick two