When I did the 350 in my 78, 40, I bought a brand new crate engine for a 78, El Camino. I also had to smog it to the 78, El Camino, 350 motor. This included a cat, smog pump, air injection and all associated vacume switches. you will also need a factory air cleaner.
Toyota LandCruiser Land Cruiser FJ40 DropDown Tail Gate : eBay Motors (item 120137314307 end time Apr-14-10 11:54:05 PDT)
real steel cruiser parts is also making them
I remembered reading some where on line, that some export market 40 series land cruisers kept the 3-spd trans through the end of the run. this was due to the simplicfity of rebuilding the 3-spd in the field. The only mention of this I could find was on this web page. LC40 I'll keep looking for...
Does it look like this, This is 653 from the toyota paint thread.
https://forum.ih8mud.com/40-55-series-tech/68536-official-color-code-thread-need-pics.html
I have both, 350, nv4500 and a 350, sm420 4spd. The nv4500 is a lot better all the way around, mine has the 6.34 first gear so i'm not as low as the 420 but it works great. With that said, if your not going to use the 40 on the highway stay with the 4spd, you already have the parts and you'll...