Unless you pop the heads, you will have to cut the pushrods to get the cam plate off, to access the inner tensioner. You can see the inner one with a small flashlight and dental mirror, but you can't change it without pulling out the cam plate and cams. As long as you have gone that far, you would be best served to replace those dastardly inner cam bearings.
For me, I would pop the cam chest, and inspect tensioners. They could be fine. Then, I would put a real, mechanic's oil pressure guage on and verify good pressure, at hot temps. No good throwing money at the problem, hoping to hit something. Just know that the oil pump relief valve could be intermittently sticking (cam plate problem). It coudl actually be a failure of the inner cam bearings. It is all a roll of the dice. Pick a direction and follow though.
If I had the green, and the time, I would go whole hog in there and go hydraulic tensioners or gear drive (even better), replace the lifters and inner cam bearings with Torringtons, add an upgraded oil pump, and be done with it. Since no green, spend nothing that is not needed right now, which requires mostly time and great care.
Yes, you can simply replace the tensioners, with what was in there, but you will have to do alot of the work required to upgrade stuff. It makes no sense to me to go that far, only to have to repeat down the road, and maybe soon, since no one really knows why the original tensioners go great then quit on you (maybe the cam chain condition). That being the case, you could eat new tensioners quite soon.
Don't ride or run it until you determine it is safe. You could toast your engine, even seize it (Danger Will Robinson!).
Good luck,
Rich P
