Most likely a JO5C TB 168HP of 5.1 litres. I think the height would make it hard to fit. You need something like a HINO N04C which is based on a 15B
When you open the drivers door, you should see an aluminium plaque like a land cruiser has somewhere near the foot step.
You should look into the weight of the motor before you get too excited. I'm pretty sure they're 1200lb dry or something. That's 200lb more than a Cummins 6BT. Too much for a 40 IMHO. Maybe even too much for an 80. You need to find one of the smaller N04 ones, or older W04.