On a 1960 261 that has 1/2" NPT fitting and lines for the standard full-flow oil filtration system, I have used the
factory canister full-flow oil filter mounted on an original intake manifold (forward to the carburetor), a remote spin-on filter head
mounted on the firewall, and a remote filter head mounted on a custom-made plate
attached to the side of the engine.
I went to the after-market spin-on filter heads because the stock canister filter could not be mounted on the dual carburetor intake manifold. For the after-market spin-in filter-heads I chose locations where I could easily and cleanly take off the filters.
In the next few weeks (I hope), I'll be putting the original full-flow canister filter back on the original intake manifold (using a single two-barrel carburetor).