I hate to say it, but if you're already interviewing and don't have any jet time, you're probably way behind the power curve. How much FTD (like a Frasca) time do you have?
Since you said -800, do you have any glass panel or coupled approach autopilot experience (Garmin 1000 or similar)? That would help.
Two things to consider: comfort with the instrumentation and the differences in flying turbine, which is mostly adjusting for the increased speeds and the automation.
If you have access to a Frasca sim, set it to the highest performance as you can and fly approaches at about 140-160 knots. That will probably help you some.