Hey guys. I want to make a Tyranitar Lead, and I got a solid Larvitar through trade earlier to work off of. Here's the important things about this Larvitar:

It's got Careful.
It's got Stealth Rock bred into it. (Also DD, but I don't know why.)
IVs are a go.

My question for /vp/ is what does the rest of the moveset look like for a sp. def wall? Is there a reason for this DD? And what's its held item supposed to be? I was thinking Assault Vest, but I don't think that's compatible with Stealth Rock. I'm assuming the EV spread involved max HP and sp. def, but some in Atk might be useful...?