I have a type IV that has been greatly modified by P/O. trying to find out what crank it has. It has K 10 VW stamped on it, appears to have the letter A on the flanges by the rod journals, but as of yet I haven't determined the stroke. Where the flywheel is mounted it has the 5 mounting bolts but has 5 smaller holes to the side of each of those, (equally spaced). Pretty sure it is stroked but I don't know how much. Any ideas by the stampings? Thanks for any help. Jon

Some crank grinders mark the crank, some don't. Many ways to stroke a crank, you have to measure the rod journals to see what rod it's made for.

If you measure the top of the main journal to the top of a rod journal with a caliper you can eyeball it good enough for a rough idea of stroke. 66mm (Stock 1.7/1,8), 71mm (Stock 2.0) and a 78 mm is likely welded stroker. Same for 80/82 strokes but less common. A lot of welded strokers are counterweighted.
China stroker cranks are not welded, but they have counterweights.

The holes are for dowel pinning the crank to a flywheel.