Try removing fuses one at a time until no smoke. Leave fuse OUT until U can get a wiring diagram and see.
LT signal not working--any lites coming on? Which one(s)? Stay on or out? Go to the one that is Out, remove socket, could be loose pins in socket causing a short. Or, wire pinched.Sometimes, bulbs short out, internally. Did U have a fender bender, lately?
Shift lockout sounds like a separate issue. U may have to remove shifter (Battery disconnected-!!) and look at wires. Most likely a switch came loose. Adjust as in a Haynes book, put Locktite on screws then retighten. Chevy ignition switches often get loose, too, only way to fix 'em is like this.