Will the RRE downpipe fit a 3" megan exhuast?

[jjaycxj]

looking to do a whole exhaust redo with my tax return but seeing as my car needs to pass emissions i'm worried about doing a cat eliminated dp but searching the forum i saw a dp from rre that has cat and im curious if that will fit my exhaust. its a Megan 3inch cat back. Or if it wont is there a full proof way to make sure your CEL doesnt throw with the catless dp?

 

[Pipnorcali]

The rre is a 3" ( starts 2.5 then goes to 3")

Check out spark plug non foulers for getting rid of cel's