I've had a look at that already on my beetle it's stamped on the block where as this is on a metal strip I've not seem one like that and if I go off the letter b it's a 1600 sp 68-70
By now all it means is that its most likely got a standard crank. And because it is running it has the right number of pistons cylinders valves and pushrods and rockers etc... Its a remanufactured case hence the tag. Anywhere up to a 1641 or even 1776. Take the heads off and measure the cylinder diameter. Look underneath and count the oil relief screws. And then you will know. Look on top and if it has rubber boots on the inlet manifold then it has dual poet heads. (Keats and Shelley sorry autocorrect) What you have is what it is now. What it was it was then.
