Y block temperature sender in right head

[bluecollarbill]

The temperature sender for the Y block in my '55 Fairlane is in the rear of the left head next to the last intake manifold bolt. There is a similar port in the right head in the same location that appears to have a freeze plug in it. I would like to add a mechanical temperature gauge as a belt and suspenders measure and I am wondering if this port in the right head is already threaded if I remove the freeze plug or will i have to thread it - anyone ever had any experience with this before ?


Thanks