In reply to Supercoupe:
The block displacement is cast onto the rear of the block toward the flywheel end, right above the passenger side inner CV. Big 1.8 or 2.0 relief casting, if you can see it under all the gunk that tends to accumulate there. The engine type (PL, 9A, etc.) is stamped into a raised flat surface on the front side of the block to the right of the block breather but that usually is harder to read because it is often rusted and/or crusted up, and is is much smaller, shallow and a stamping.
By the way all the Golf and Jetta 16V sold new in the US were CIS. The '87-'89 were all CIS-E (officially KE-Jetronic) and the '90-'92 were CIS-Motronic (officially KE-Motronic).