Lexol is a mixture of neatsfoot oil, some other oils, and waxes.  The
wax gives you a nice shiny surface.

Ace Hardware carries it.  Personally I prefer using the "boot oil" from
Red Wings shoes... it's a little thicker and takes longer to soak in, but
it's a neatsfoot oil blend that seems to last a bit longer than the usual
neatsfoot oil.

Note that neatfoot oil and related products will darken leather.  Depending
on the finish, it could darken it a whole lot or just a little bit.  Also
note that if you have really old leather, it may take a few months worth of
weekly soak-downs with neatsfoot oil for the stuff to soften up.

Hit them with the oil and keep hitting them, but give it a couple months
before you give up on them.
--scott

Getting the leather warm, say in good sunlight or with a hairdryer will
speed up the absorption process.  Neatsfoot oil, not the compound,
works very well.

Sounds like you're all set, LOL. Cool. Actually, your use of
lanolin-based treatment works well for leather. I'd be very hesitant of
a hand cleaner, though, as the detergents and de-greasers don't help the
leather fibers and will weaken the fibers.

But, any high-percentage lanolin lotion/oil/wax is good. Leather treats
lanolin as a natural oil, although it doesn't absorb as quickly as a
neatsfoot.

You want the treatment to get into the leather, not just moisten the
surface. The surface is finished, as a result, the treatment needs
absorption time to get through the finished surface to the underlying
fibers where most of the stiffness is occuring. This takes time and
several applications, especially since you can only treat one surface,
where I usually treat both sides of my leatherwork to speed things up.

Even though you have a black interior [which makes things much easier,
LOL], you want to control the absorption process. Otherwise, some
darker areas may occur. [Not too critical for black, but thought I'd
mention this]. And, since you have nice weather, absorption should be
quick.

I control absorption by applying the treatment, let sit for around 3-5
minutes, and wipe off excess with a soft towel. Leather has it's
natural absorption rates, which differ across the leather hide. Your
conditions seem to indicate 2-3 minutes.

Then, re-apply, and repeat for a few times. Let it dry [absorb]
overnight, and check how it looks the next day. Repeat process until
desired softness and colorization are to your liking. Getting the
leather soft will most likely darken the color noticeably.

Products like armor-all, maguire's, saddle soap are primarily good for
surface after-care, but ineffective in penetrating to the fibers, where
you need to get to.

Most horse-tack cordwainers use neatsfoot or some lanolin-based
paste/oil to soften their tacks. Oil for the primary softening, and the
paste for after-oiling through the leather's usage. They also try to
keep the leather warm, around 70-75 degrees ambient, to maximize the
treatment. Too low, lower absorption, too high results in spotting.

Sorry if this is a bit long, but I've had great success in leather
conditioning with the above. And, as you posted, I'm taking your query
from reconditioning a very dried-out leather cover, not a general
shine-up.