-8 jic cap for oil tank inlet when purging oil system?

Yes, the yellow plastic cap that came with it will work.

Any hydraulic, tractor supply, or fittings store can sell you one, metal or plastic. I bought a brass one for durability.

Hi Steve,

There is absolutly no need to remove the metal OIL IN curved spigot - just remove the the rubber oil hose. The spigot can be capped by any handy plug/cap, including a short piece of rubber hose that has been blocked (turned into a cap). There is no need to go to the trouble & expense to have a threaded cap that will have very infrequent use..

Off topic observations -

It may be the camera angle, the video aircraft would appear to have one of the most difficult oil filter removal situations, I have seen.

Looks to be the fuel pressure sensor is below fuel reticulation system - should be above.

Left side radiator coolant hose would appear to have a series of unnecessary joins - hose joins should always be kept to a minimum.

Weird oversized SCAT tube drains hose on carburettor drip tray😈