How do the timing marks line up on a Mazda B2600?

i am changing the timing chain on a 1991 Mazda b2600i pickup %26amp; need to know how the timing marks on the gears are supposed to be set %26amp; is it on exhaust or intake stroke?How do the timing marks line up on a Mazda B2600?
the old mazda b series 4 cyl. had no timing marks.you just split the lobes on the cam ,pointing them in the airand roughly even.the crank was set at tdc,what a pain with the timing chain tensioner.if you slacked off the timing chain to much, the tensioner would pop out and into the oil pan.was never ever recomended to push start them as the timing chain tensioner could pop out if the motor slightly turned backwards.