Lenovo W540 (aftermarket) storage options?

Hello. As of this week, a new owner of a fine W540.

Since I need lots of storage space, I'd like to confirm with others what can be done about it, aside from the main SSD slot (currently a 1TB SATA3 SSD in mine).

I guess the optical is replaceable with a HDD/SSD caddy, and it can only take 9mm disks, since the caddy is 12.7mm?
Is there any other expansion option? My w540 is without the WWAN, if that matters. I do not know how to check if it can fit mSATA/M2?

I could not find any full info on all storage options, which is why I'm opening the topic, possibly on something already said. My apologies if it is a repeat, I did not find much via Google on the subject, mostly review sites making vague remarks.

 

Noone?

 

Hi alfaunits,
You can install mSata m.2 hard drive remeber that you need to have 2242 model which have 42mm height. You can find them in 120GB and 256GB. Not sure if m.2 2242 are coming with higher capacity.
Drive bay will fit 7mm as well 9mm so all 2.5" hard drives will match.

 

There are 12.5mm and 15mm 2.5" HDDs as well. I somehow fit the 4TB 2.5" 15mm in my VAIO F1 But the Lenovo W540s caddy is too slim for it, so ti will have to do with 2TB.
I found 512GB m2 2248 here in Europe, but it is too pricey for now, so I'll stick with 1TB SSD for the time being

But is this all, nothing else I can expand with?

I've been thinking of getting 2 mSATA SSDs, get 2x mSATA to SATA adapter, so I can put 2 mSATA in the SSD slot, if needed.