Replace dried out grease in a vintage Elgeet 13mm f/1.5

I got an amazing deal on a “for repair” Elgeet 13mm f/1.5. The problem with this lens is that the focusing mechanism is nearly frozen. Aperture works great.

I was wondering if anyone had a diagram or instructions on how to open this lens and replace the old grease?

Also, what are things that I need to be aware of when I open a lens? I have never done this before.

Lastly, what kind of replacement grease should I use?

Thanks!

Mostly I'd say don't. Send it off or wait until you or someone has the money. So many ways to foul things up.
If you have to though: One of the challenges is going to be keeping track of the alignment of the helical spirals. They fit together many ways often.