Valve spring heat insolator on intake side

I have noticed on my RH10, 850 Head, when doing a rebuild, the intake side of the valve spring stack is missing the Vave Spring Insolator Washer on both sides. Not sure if this is needed or intentially missing. The parts book does call out for one being there, part # NM233292. The guy that last built this head was a seasoned expert, so thought I would ask the forum and see if others have run into this.

As i understand it RH10 heads only had insulator under the exhaust valve springs so your head is correct.