I have an old BB 318 thats missing the timing chain cover. Can I use the newer style from the late 60's to mid 70's? Are the bolts holes the same. Thanks!

first there is no such thing as a wide block, and the covers are different,

but i am sure they will work, i think the only thing thats different will be timing locations,,

if im wrong please corect me..

you are looking for a pre70's timing cover if you are planning on using the pre 70's pump.
Should bolt up just fine.

lots of stuff swap over t-chain cover being one of them

they are good canidates for a ssteel crank for the LA 318 also

LA will bolt on the same tranz and vice versa

You need the pre 70's smallblock cover to match the timing mark location on your early harmonic balancer. If you use a later cover, you need the later harmonic balancer, and of course the coresponding years waterpump.