40 years ago there was no "assembly lube"(except that supplied by crane, isky etc for the cam) and motors worked just fine after starting up. I would use it if I had it, but wouldn't let it stop me from doing something. Use a quality oil and coat all the moving parts.. I also fill the oil filter if it is in a position that you can before I crank the engine, I also do not place the coil wire until I have oil pressure and usually leave the spark plugs out so it turns easier while getting oil pressure the first time. Don't know your experience, so I'll mention that most engines drive the oil pump with the distributor, so it has to be in place before you try to get some oil pressure. I always check clearences when assembling.