there's a timing belt tensioner just like your serpentine belt tensioner. probably almost half way down the block and most assuredly a pain in the arse to get to on a transport. it'll probably take a 14 mm wrench to loosen the tensioner.
just turn the motor to where the timing marks are lined up to the motors spec then loosen the timing chain tensionr. it might be wise just to replace the timing belt since you have it tore down that far