Quick carb rebuild question

[Jcab256]

Hey guys.. I've been a lurker for about 15 years or so. I recently purchased a 72 GMC camper special the 402. It runs, but not great and I’ve tracked it down to being an issue with the carb. I disassembled it to do a simple rebuild on it, but noticed something potentially concerning. I don’t know if it’s flaw in the casting, or if the casting is broken from someone prying on it previously. On the main body in between the secondaries, there is a hole that goes through the back of the casting. The exit point looks like a break, and not factory. However, this is the first time I’ve ever taken a carb apart. So my question is, does anyone know if this hole is needed, Or if I can be a epoxied closed or..... The first picture shows the hole I'm talking about, and the second picture shows a small wire but I pushed through to illustrate the hole to the outside of the carb

Thanks in advance