Yeah me and my father are likely going to put a 14B or 15B into an '84 LN65 Hilux. As per a question I asked a while ago:
http://www.outerlimits4x4.com/phpBB2/vi ... p?t=118813
My father too can get an entire BJ40 cruiser (rusted to hell) with 3B and for a carton, but wants the 15B.
I was looking at the Toybox idea, but decided it was too much money for what we would end up with. We have a solution for the drivetrain, but still will be using Hilux parts, no landcruiser parts at all. We found oursleves a late model gearbox we did not get to see the donor car though. I believe it is an R151f (take the extra torque better too) with chain transfer, also has the vacum 2-4 switch etc. This will near straight fit into the car, and tailshafts might be alright (we're getting new rear one anyway). The R151f fits to the B block, if you get the correct bellhousing (BU85 Dyna), and make a couple of angle grinder mods.
Engine mounts could be an issue! We have not delved into this deeply yet, but We think we might know a way to get some adaptors going on the engine block.
Dont have the slightest about body clearance for the larger engine, but the body will get dropped on the chassis later, so anything that fouls will be rectified as necisary.
from what I've read, the G52 pos will not hold up to as much torque as a good B block should churn out, so the transmission swap is a must. The axles should hold up, we've taken the step of putting an air locker in the rear, and LSD in the front which are both stronger than standard open centres. If the axles themselves give any curry, then some after market heat treated jobs will go in there quick smart.
And suspension, do not neglect, I did have weight differences between a 2L and 14B a while ago but cannot remember them. I think the 14B was around 350kg? anyone... ANyway we had custom front springs made to suit by carrolls, and we moved the front axles foward and inch (in the custom springs) so as to throw the extra weight backward and not too far over the front; this also allows slightly larger tyres to fit with less work, a nice little bonus.
This is all theory, we dont actually have a motor yet, and my father who is rebuilding the beast has taken 3 weeks to meticulously rebuild the axles, so it will be a while before the engine goes in. He is very thorough and fussy.
I heard as second hand info that a Hilux who ran in the 2007 (still this year for another few hours) outback challenge was running a 15B, but dont know much about this. Might be worth chasing up...