Find the Norton equivalent resistance

[messier992]

Homework Statement

Find the Norton equivalent resistance

Homework Equations

Sum of resistance in a parallel circuit: 1/Rt = 1/R1 + 1/R2...
Sum of resistance a series circuit: Rt= R1+R2...

The Attempt at a Solution

Don't know where to go from here:

 

[messier992]

Actually, I believe this might be the solution. Is this correct?

 

[Tom.G]

Well I see you got a start and eliminated the Voltage and Current sources. However I can't tell if those sources were replaced by Shorts or Opens. Can you clarify with a better schematic?