Re: installing new engines
yes definitely. And if I'm not wrong, it's gotta be done by the authorised dealer. If not, you might still get it passed by LTA but i'll imagine a lot more headaches. So, if your engine is very old, going to go soon, something wrong, water went in, etc, you can always get the engine changed out in your free time. It's like any other car component. There's no other tax to pay other than GST. Actually even if your engine nothing wrong you just want to spend money to change it also can, in theory.
Now, if you have a 6yo car, and the mileage is very high, but otherwise no problem. And if you're intending to buy a new engine already, why dont you drive it until it totally piang, then change. might as well right?