Info regarding Engine change.

[sheraz2000]

Hi guyz, i have been using my vitz 1.0 auto for about 8 months now. everything is smooth and perfect except the SLOWW engine. today after a long search i found a replacement engine 1.5 (without a gearbox) but its in another city. i dont know the details on that engine yet. but the price tag is preety decent. the engine is available along with all the genuine wirings + the computer kit. Any help into what i should look at. which engine model is this? can the engine be changed without any fabrication? i will be using the same gearbox that i have in my car now. Can it be done, should it be done? Please help. suggestions etc.