Re: SRT6, Locked up but not blown up???
I don't have exp. with SRT's, but lots on eng., troubleshooting and rebuilding. To answer if an eng. has locked up, try pulling the plugs and then rotate the eng. with a wrench on the crank. This is safest. With no compression, the eng. should turn nice and smooth. DO NOT try to turn it over with the starter. Turn it over with a wrench, If you dropped a valve or something stupid, you'll feel the bind while turning it by hand. Turn it slowly. I am not sure what turns the supercharger on an SRT, but if it is belt, chain, or gear, and you can access that area, as you turn the crank, watch for a bind in that assy. You should have no problems finding what is stopping you from turning the eng. over. You can also remove valve covers to watch valves operation. You can also use a plastic Mc Donalds straw to slid down on top of the piston to feel it's rise and fall within the cyclinder, just becarefull not to pinch it while inside.
Also access to a bore scope, you can see inside the piston bores. What's the eng. oil look like on the dip stick? When removing the plugs, are they wet with oil/coolant? Could be hyro-lock, if so, don't try running the eng. A blown head gasket can leach coolant (over night) into a cylinder causing the eng. to lock up. If eng. starts, water has to go somewhere or make it's own path, and that is NOT pretty.
Hoping it's something simple and stupid for you. and NOT a locked eng. A locked eng. is never a fun (or cheap) issue.