Db8 - Yea I have been thinking that too, I haven't quite finished pulling it out yet so once I have and have worked out what's gone wrong I would definitely look at just that - if it's cheap enough to fix up just do that and keep saving for a rotary.
My other way of thinking though is i'm really sick of cruising at 85kmh and would love something with a bit more pep. If anyone had come across a bolt out/bolt in replacement not requiring too much dicking around and not going to cost me too much I would still be pretty keen to look into that.
Or, if its going to cost to much to fix for now I may also just park it up, pick up a cheap runabout and start slowly getting it ready for the rotary.
Metalhead96 - Had considered using an engine from some of those older series, had been looking most seriously at an F6a turbo as I understand they would bolt straight in. I don't know if the LJ50 would give me quite as much power as I'd like, from what I can see they'd be about half the factory hp of the F10a whereas the turbo F6a can give a bit more. The only problem with that I think would be that mounted tilted like I don't know if it'd get enough oil up top (especially being DOHC instead of SOHC) without a bit of playing around. I don't know though...
Bwarp - Is that a caffeine fueled weekend in a fully stocked workshop with an army of mechanics?
Threeonthetree - Will do, thank you
R100 - Yes unfortunately I am aware of that Would be looking at doing the lot though, want to make sure it's safeish too. Wider axle, new brakes, new diff, new gearbox, lowered and sitting wider, the list goes on and the price adds up.. That's why I keep coming back to them, perfect size to fit in! I mean when you start with a 1L that's barely squeezed in there on an angle it doesn't give you too much option to try fit more grunt easily. Had thought about trying to attempt a mid mount but would prefer the engine under the seat - leaves more room for subs in the back