Possible - yes with $$$$ and months of time by a shop who's willing to figure out the electronics (if one even exists) - but I'd personally just get another LC200 or a LX570. Or if you really want something in Nori Green with a V8, get a 2022-2023 GX460 instead. GX550 money can go a long ways on purchasing a 460 and modding it.
Like anything, it just takes time and money. You'll enjoy the power of the 6TT, it just delivers it differently than the V8. I wouldn't bother with D60 conversions when the portals are out there and proven for $20K, no need to re-gear, clear 38's, no modifications needed to do an IFS>straight-axle swap.
Just watched a video of a guy clearing 285's (big 34's) with no mods or trimming on a stock OT, he simply removed the insanely huge KDSS line cover in the front driver's side rear wheel well. There's definitely an opportunity for someone to make a slimline guard for that as well.
besides the twin turbo six blowing up (lmao)
the new v6 makes more power
delivers more torque at the lower end
and it has tuning potential in the future
there is some wizard out there that can marry the two but imho you are pretty much downgrading unless im missing something about the old 5.7 v8