I am hoping someone may have some information that can help me. I recently purchased a Condit modified (pin registration) 4500. I want to un-modify it. There were two shims between the lower negative stage and the main body of the head. There was also a negative carrier housing between the lower and upper portion of the negative stage. The carrier came out, no problem. The shims came out, no problem. But when I bolted the lower portion back onto the head, there is about 3/8" more space than the standard negative carrier. Is it possible that there was something removed from the lower portion of the negative stage? If so, what is it that fills up the balance of this space? Any help, or even a picture of an unmodified enlarger would be great. So far I have not been able to find detailed information or photos of an unmodified enlarger. Thanks!