Now that I'm on the computer and not my phone I can be a little more clear.
If your Premiere has 50 AMP service, it is essentially a 220V camper but there aren't any breakers which run across both hot inputs. 50A RV service is 2 120V hot leads with a neutral and is the same as in your home. Each hot (labeled line 1 and line 2 in the diagram) is 50A, and feeds the circuit breaker panel exactly the same as how your home is powered. Hooking up the generator would be straight forward using both hot leads from the generator:
And the RV plug:
So using the pictures above it would be wired:
Neurtal (white) to N
Line 1 (black) to L1
Line 2 (black) to L2
Safety Ground (Green) to G
and for 30A
Neurtal (white) to N
Line 1 (black) to H
Line 2 (black) NOT USED
Safety Ground (Green) to G
Be sure to use at least 10 AWG which will be protected by the 30A breaker on the generator.