Hi and welcome to the site. Lots of talented guys here that I'm sure have all the answers you'll need to do the LS swap successfully.
If you already have the LQ4 and 4L80E, your battle is half over. The only thing I can think of besides the usual motor mounts and wiring harness stuff is that you may need to change/shorten your drive shaft due to 4L80E's longer overall length and different yoke compared the manual that is in the truck now. Probably a few other minor things I'm forgetting.
Believe me, go with the swap. Sure, it'll take some work, but the rewards will be well worth the effort.
'93 Chevy 1500 4X4 ECLB with a '99 Silverado LQ4 6.0 and '99 Escalade 4L60E. SOLD IT!!
New toy: 2001 2500 HD 4X4 Extended Cab Long Bed
John