should be a triangle sheet metal piece that goes behind the lower bolt with a locking tab on the 4th hole to drip oil on to the chain

the hole in the bolt is early and the drip tab is a later set up

an engine oil cooler would use a hollow fuel pump bolt and spray oil directly onto the chain

the tensioner you have is for a late model engine

not sure if the tensioner is gonna use either of the oil set ups

it will get oil with out either one from splash and from the top holes in the vally part of block

maybe some one running the tensioner will chime in on the drip tab

i dont think its used with the tensioner