The Tech-Tip on oil filters would not have your filter in it because the article is about by-pass oil filters.
As you most likely have assured yourself by now, you have 58-63 261. These engines had a full-flow oil filter system (just like the one in your photos).
The lack of an engine serial number is probably because your engine is a factory replacement engine - the installer was left to put the original engine's code on the block, in case that code was used as the VIN/Title/Registration code.
Several people have posted photos of remote filter assemblies used with 58-63 261 engines. Do you want people to post links?
If you are switching to a remote filter only because of leaks in your filter assembly, where are the leaks? If the leak is at the top of the canister, I think that replacement filter-cartridges come with a new o-ring.
That original filter set-up is impressive-looking, effective, and a great conversation piece (especially with GMC engine owners who like to slag Chevy 6s, even though all GMC 6s had by-pass filters).
Tim
