I'm working on the same project myself. Although, I'm also doing a full resto on the FJ40 at the same time, so It'll be a very long term project.
I've already got the 4bt, a Dodge Engine Adaptor, and Dodge bellhousing for a NV4500. Behind that I plan to run a AA Adaptor to run the FJ40 Tcase, because I want to keep the offset rear diff.
I set my rig up SOA to have enough oil pan clearance, and also to run 35's to
keep the RPMs down.
You can check the progress so far at my Blog in my sig. I suspect it will be late summer before the thing is running.
On your original question, I have not seen any pics of a 4bt in a FJ40, but I've heard it's been done. I seem to remember someone on Pirate4x4 did it, but now you have to pay to search, so I can't find it.
I am also doing this conversion. I think I have everything ready to go. Mine will be 4BT HE351 turbo, GM nv4500, Stock J30 t-case. I dont see why the stock transfercase wouldnt hold up, Probably depends on how it is used. Mine wil be mostly used on pavement.
Yeah, the J30 hooks up behind the toyota 3speed. Ive got the 4 speed with the H41. I believe that they are both strong enough, but i think im gonna with the splitcase behind the NV4500. But i really like the parking brake on the tcase like the H41 H42 and J30. How are you going to hook the J30 to your tranny?
I bought the AA adapter housing that bolts on the rear of the NV4500 inplace of the overdrive housing. Works really nice. I have it all hooked up, I was going to convert to a 4.3liter v6 and got 99% of the way done (it was even driving.) Then I found this 4bt and decided to start over.
Yes I still have the OD, the adapter just takes the place of the aluminum casting that bolts to the back end of the transmission, the gear cluster stays in place. The OD ratio of the NV4500 is .73. I think this is the same OD for the older low ratio 1st gear and the high ratio 1st gear transmissions.
Check with AA. I dont know how mucht the adapter costs, its been a few years since I bought it, but 640.00 sticks in my head as what I paid for it. Not cheap by any means but it does make for a clean install.
I was just BSing with one of these guys backchannel about the early 3 speed t case. A lot of guys run these behind 350s. They do break though, mostly on the trails, the t cases are a little brittle. If you do run one, make sure its (I think) 1970 or later as '69 & earlier are super brittle. It is the case not the gears. The the "t case saver" that some guys sell on mud helps a lot too...
HEre is what I wrote & think about it, if it helps..
The 4 speed case should probably be OK.. They do break though, mostly off road.. My only beef with them is honestly noise, they have a nasty little gear whine to them as the gear cut on them is old school. IF oyu are going to get a NV4500, you can choose to adapter to whatever case you want for the same price. Only additional cost is the actual case. Shop around, you can find a FJ60 era split cases pretty cheap. That is what I would do and run a FJ60 rear axle, slightly wider, and has the e brake on the rear axle, then you are nicely set up.. Hope it helps! Andre