Tauhu Tauhu, the website is not true to say that 4AGE weights only 6kg lighter than 3SGTE, that is not possible, unless if they measure engine kosong only, but even engine kosong also weights much more than that. Last time when my friend did his conversion, even the engine jack was nailed down into the earth, you say la how heavy is the 3S.
3S engine, possible to squeeze in an AE111, but would be a very tight fitting that means, changing any beltings require you to remove the engine from the bay and putting it back. As an example :
http://zerotohundred.com/forums/uploads/post-8-1105943108.jpg
And by putting this at the rear however, you get to enjoy the traction of a 4wd.
http://zerotohundred.com/forums/uploads/post-8-1105943290.jpg