Some perspective, my dad started out with a dennis steam truck, but he also rode stuff like rudge ulsters, his mate had a vinnie, rode bikes on and off most of his life, got his steam and electric tickets amongst others, and ended up chief engineer for south east asia for a well known international shipping / oil company.
He always maintained (with the exception of silicon transisitors and new plastics) that the only two significant advances in engineering, particularly as regards to vehicles, since he was a lad were tyre technology and lubricant technology.
Nothing I have ever found has proven him wrong, uncountable examples of him being right.
Lube oil is horrendously complex stuff to understand properly, it has MANY MANY different characteristics, ALL of which have to suit your engine, and yet the only info you get is a brand name and a small type number, eg Castrol 20W50 (diesel)
Listeroids are not listers, so YMMV
Listers were designed to use a lube oil that dropped all the crap out of suspension in the sump, and come oil change time was used added to the engine fuel. SO that means a NON DETERGENT oil.
Multiweight oil is not multiweight or multigrade, ALL OF IT is monoweight oil, with certain additives that under certain circumstances make it perform like a multiweight, but the reality is it is ALL the lower of the two weights quoted, with additives, which if they aren't working for whatever reason = mono weight oil that is not pure, so with a lister or a listeroid given the relatively low stresses involved never use a multiweight, cos you'll never push it into working properly.
Synthetic oils are another thing entirely, but they again have a performance envelope, and unless you can find one expressly designed for a 4 bhp per litre 650 rpm diesel, which you wont, don't use em, cos if you do they will always be operating outside their performance envelope and may well give less protection than worn monograde diesel non detergent oil.
Lubrication is a funny thing, you don't actually want the best lubrication possible, in the slippery sense, because if it is too slippery it won't stick to an uniformly coat the bits you do not want to wear.
___IF___ you have a motor car style full flow oil filter use a monograde detergent oil.
___IF___ you do not have a motor car style full flow oil filter use a monograde non detergent oil
if you have TRB or plain mains it makes no odds, you still have plain big ends. If you had TRB mains and needle roller big ends AND camshafts then I can see a synthetic oil being useful, cos plain bearings load oil a LOT less that rollers, rollers are approaching hypoid oil pressures, there are no such extremes in a standard lister cs
HTH