308 engine lubricating system

So I have oil pissing out of a gallery plug situated behind the tensioner bearing (oil filler cap side head) it's alloy and it's Allen/socket head type i would imagine that it's gonna be wee bit on the tight side being that it's been in it's present position for so long and it's alloy. Has anyone ever had the same problem as i have is the plug tapered or standard thread, what sealer did u use on the plug, the new plug is on it's way to me from s/formance uk hopefully the factory used the same size plugs throughout the entire engine as S/P only list the 1 size plug. Thanks in advance.

 

If it's in the head, since that's the only one in that spot. I've never had them out, nor tried. most are pretty much 'welded' in over time. may have to drill it out and re tap the hole. But since it's leaking oil it may not be hard to remove.

As for how to seal it, use anaerobic sealant if it's not a tapered plug, if tapered a little thread sealant paste will do.