2002 2.7l 5 speed timing chain tensioners??

hey guys and gals, im suspecting my timing chain tensioners are going bad. engine runs great at start up, and goes good down the road however when it comes down to an idle, theres a very noticeable ticking/tapping sound and engine runs a tad rough. i was thinking lifters... then someone said its more than likely my timing chain tensioners are worn out causing it to slap. how do i go about checking that and possibly fixing without pulling the engine? i have a spare engine i can take apart to see how involved it is but the noise if defiantly coming from the front of the engine. as soon as i touch the throttle the stops tapping. even does it it with acc belt removed

 

or should i just look for another engine?

 

what about a new hydrolic tensioner? if thats not enough, i know it sounds crazy, but what about welding a small nut to the end or something to take up some room? i took the one out of my spare engine and it seems to function correctly, i pushed out the old oil and put it in a container of fresh oit and worked it in and out.