Tolex is a vinyl, and not need the same care and cream/oil used for real leather. There are some products to use for plastic that are good for tolex.
I use this https://www.innotec.eu/oth/en/products/multi-spray-1000/p1205
I have a Marshall cab with 8 ohm V30, and is really close to the Mesa OS of my friend; mine is straight his Mesa is slant. Lynch not use his signature speakers?
He has done much more than that. I remember in the old HRI forum he was promoting his stuff a lot, and even posted a chart about cables and plugs; he was claiming he had those made especially for him, which were a lot better with lab tests to prove it.
Till someone removed the sheath and...