I'm looking at buying me a pair of illusion audio luccent L6 component speakers for my 08 nissan 350z. I notice the mid drive mounting depth is 53.3mm and would like to know. Would i need spacers for these to fit in my door's or can they go in without any ?

 

You will likely need spacers.

Save the old speakers. You might be able to use these as spacers by cutting off the mounting ring.

 

Get the spacers from ZEnclosures (see THIS thread). I suggest you spray paint them before you mount them since the area these go into is prone to water intrusion and they're made out of MDF. I put a couple coats of black Rustoleum on them before they went on and 7 years later they still look like new.