For sure I would get the first:
- I think it has the long column and the large baseboard, the second Ic has the short column and a smaller baseboard
- the lens of the first Ic is the Schneider made Focotar 50mm, which is the better Focotar (with the Focotar-2 50mm) and for sure much better than the 5cm Focotar of the 2nd Ic
- It was rewired
- It looks like the first Ic will have the clamping system for the Leitz easel underneath the baseboard, but this may lack the lever sticking out on the right side of the baseboard (it often does). Ask!
- Both enlargers have no filter tray or holder. It is easy to solve this
- The second enlarger has the Anti Newton ring for sure, ask if the first does too. I think it does show it has in the last picture
- The adapter baachitraka speaks about is in fact an extension ring that drops the lens down by 1cm. It should be there. It has either 17675 or DOORX marked on its side
- both have the negative holders