guyz the mk2 cortina is small like a datto 1600...
this conversion has been done a few time actually i'll try find an article in one of my mags i do remember reading about it though, so you have the head start there with knowing it can be done... and i'd reconmend asian auto spares in slacks creek QLD or Jap performance
if i remember correctly it actually sits in there quite easily...there is a heap of room under the bonnet for it!!!
i don't know how wild you want to go with this machine but i so love the idea of the 20v 4a but again depends on what end resault your after...
ohh and also you can get the half cut outta the is200's apparently they have around 150-160 kw and are 6 speed but i thing these are expensive let us know how you go....