301 Question

I have a small issue coming up I hope someone may be able to shed some light on.

DOMAIN #1 - 8 years old, but in six months will need to be shut down due to legal issues. It has 50 products.

DOMAIN #2 - 3 weeks old, has 1 product from DOMAIN #1 and specializes in that one product (that remains legal).

Question - When i shut DOMAIN #1 down should I 301 the entire domain to DOMAIN #2 or just the 5 url's for the 1 (and only) product DOMAIN #2 has?

Or 301 the relevant product pages from #1 to #2 then a site-wide 301 homepage to homepage?

Domain #1 is very successful and has excellent positions and a clean backlink profile, albeit for products that will soon no longer be available on the clear web.

Thanks!

Anyone?

can you even 301 a domain that you don't own anymore?? I can't see how this works...

Regardless, I wouldn't 301 anything if it's a legal issue. Better be safe than be sorry