^ Now that I've got a 5.3 in a '93 245 I got specifically to do the swap, I want to do something like an LFX or Ecoboost 2.x to give my '80 245 a reason to continue existing. It'll be a few years before I'm ready to bite the bullet, though, lol - it was a long, taxing, build process, and I've got some other smaller projects in the queue ahead of that.
Compare the LFX to a 5.3, not a 6.0. Especially the lower-compression Gen. 3 variants like the LM7 and LM4 have similar power numbers, only swapping ft-lb and hp numbers between them.
The thing to watch would be the driver side downpipe clearance - it might exit right into the steering shaft, which would be hard to build exhaust to avoid. There's no solid measurements on the internet, but I suspect the LFX is 1/2" to 1" narrower, which wouldn't give much room for a clean transition, if it's in that exact area. Some of the V8 swappers relocated the steering shaft; a lot of us filthy casuals using STS mounts and Holley cast manifolds just used available wiggle room or switched to solid splined shafts.
If GM were going to start doing connect-and-cruise or E-rod packages around a V6 (and really, they won't - they've even dropped the 5.3 E-rod, nobody doing that much work wouldn't rather just have the 6.2. They probably sold just enough of them to pay off the CARB certification process), it won't be the LFX, for sure - it's already been superceded by the LGX. Still, it was available in pretty much every USDM GM product except the compacts and full size trucks, so it should have pretty good junkyard availability. Also came in RWD, maybe even with a manual option, in a Caddy or two (ATS / CTS). It wouldn't be a "drop in" package, nor would it be from the "Chevrolet Performance" catalog specifically, but if you had to do it using new parts, I'm sure you could get all the involved parts new from GM, through a dealer like Tasca. An engine from something like an Equinox + a modded pan from V8roadsters + a
fresh transmission might also be a winning formula.
Rapid edit: They show that part number as fitting both the 3.6 and 6.2... maybe not!