Three cam jobs in LT1s ranging from 65-142K miles used whatever oil I was going to use in the engine 5w-30 or 10w-30 of whatever I choose to use that week. These were all fired fairly shortly after the install though, if it will be weeks or something then I would make the effort to get assembly lube.

If using something else I would say use assembly lube, if you concot something yourself do you know enough to make something that will wash cleanly once oil starts pumping???????