What problems could occur when switching 4 bbl carburetor to a Holly sniper pro injection kit?

You will not run into much. This kit is extremely easy to install. The throttle body will pretty much bolt right into place where the carburetor is, but you will need to install a temperature sensor and o2 sensor. This is not that hard, but I would suggest reviewing the video below directly from Holley.

https://youtu.be/nqfByzI6gJE

Clearly there are other videos out there but if you follow this video and the instructions, you will have no issue.

Once you get the wires run the rest is just plugging it in so, please review this video and let us know if you have other questions.

Due to not knowing the condition of the engine, I would do a compression check before getting this installed just to ensure you are putting it on a sound engine.

https://www.2carpros.com/articles/how-to-test-engine-compression

Let us know how you make out.

Thanks

Haha. That is an endless discussion and I highly doubt you would get two people to agree. So, if you went with this system, I think you made a great choice. Any of these systems are going to give you reliability but this one, like others, gives you the look of it is still carbureted and you don't have to change your intake manifold.

This does remind me that while it should bolt on your intake manifold with no issues, if it has a different bolt size, you can just get an adapter plate. This is basically just a plate that bolts to the manifold and then gives you the correct bolt spacing so that this throttle body will fit the manifold. These are available all over the internet.

Good choice and thanks for asking us your questions. Please update when you are finished and post pictures! Thanks