[Wayne 962]

Ehh, I'm not so sure that if you do this, you're in deep poo. You can loosen the tensioners and then move the shaft with your hand and put the cover back on. Then, recheck the timing. On the 5-chain motors, the timing is not likely to jump. If the timing looks good, then rotate the motor with a wrench, taking care to pull the plugs and make sure there is no resistance as valves open and close (they might be tapping the pistons if you're not careful). If all seems okay, rotate the motor back to TDC and check the timing again. If the timing is visually okay, then you should be all right.

-Wayne