From the pic’s it’s definitely a bypass setup and you have the return marked #2 I. You can keep it bypass and use a spin on or use the original style bypass or plug it altogether as it was previously run. Only the pressure gauge was hooked to ?. Personally I’m an Amsoil fan as it grabs particles down to 2 microns. I mounted mine on the oilpan like this. Good luck.

Curt B.

1952 Chev 1300 Cdn. ½ ton