where is the year location on a LT1 motor because had a problem with switching the ditributor
now the one i hve wont fit

 

The year is part of the VIN stamped on the block at the back. See Shoebox's photo. Note proximity to oil filter:

http://shbox.com/1/block_vin.jpg

If your cam has a long dowel pin, and the hole in the timing cover is "large", its a vented (95-97) unit. If the hole in the timing cover is "small" and the inner diameter of the hole in the cam sprocket has "teeth" to engage the Opti driveshaft, its an unvented (93-94) unit.