when the marks on the cam line up, you can put your flywheel on with the BB on the pointer. If you can't get to the cam, just get 1 and 6 on tdc or at least close. (they will both come up at the same time.) then you can get a good idea whether or not your flywheel is in the right spot. It will be close or way off. the 216 distributor should be a direct exchange. As long as it is out of the truck, this would be a really good time to remove the sheet metal parts, and check things out before you go to great lengths to install the engine just to find you have something wrong, and to insure you have a leak proof (or something close to it) engine. as well
