B-R-T

you got that right if you stall - get a bicycle ;) you'r not ready for a car :P

You right, they last longer, but they dont give "great ignition". Because you dont NEED "great ignition" on stock non-turbo engine. And spark plugs are not generating spark. Ignition coil does. If you want "great ignition", put aftermarket coil(s), new wires and make a better ignition timing map. IK16 gives same spark as the K16 plugs, they only last longer.

Rev limiter is a ECU function. Tachometer only shows RPM, it does not control rev limiter. It will kick in anyway. Unless it was removed.

Throttle?! Vacuum?! WTF?! No offence, but.. ..well.. you %&@# It have to be the mounts (If RPMs are steady) or idle valve (if RPMs are jumping at idle)

Its not to hard. You just have to remove the auto tranny (first remove driveshafts from wheels and be careful when removing driveshafts from tranny, because when you remove them, the oil will leak from the tranny, so you better drain the tranny before removing driveshafts), then put a clutch disc and pressure plate on a flywheel (if the flywheel doesnt have holes for pressure plate bolts, you have to get other flywheel), then put the manual tranny on engine. Dont forget to put the release bearing on the imput shaft, before puting ir into clutch disc. When tranny is in place put driveshafts into the tranny and into the wheels. Then fill the tranny with the oil (i'm not sure what kind of oil, because i reused the oil which I drained before). I filled my tranny through the back up light switch hole. But i think you could use any hole. Then you have to put the clutch pedal and cylinder with the lines, the shifter, cables and other stuff. I'm not sure that speed sensors are the same. You have to figure that out. ;) Its not hard, you just need some time I'm not sure about the engine/transmission mounts. I dont know are they the same. And if the engine vibrates a lot, then you have to get you pressure plate balanced.

You dont have to wait overnight for your car to cool down. Wait just a few hours until it cools down. Fuel pressure will not drop with temperature. When it cools down, put something under the FPR ant remove it. Just do it slowly. There will be some gasoline coming form the rail, but not too much. I suggest to do this job outside, because of the gasoline fumes. And its better to disconnect the battery when you do the job. And of course.. Dont smoke ;)

Rims looks good though. But I suggest to lower your car a bit it. It will look much better.

it depends on how much money you want to put in your car. any car can be powerful. 1ZZ-FEs "top" is about 380whp (with forced induction @ ~28psi, without N2O).