AvalonMiner DIY Controlboard

I recently got an AvalonMiner 741 from a friend that was cleaning out their garage and is really into mining. They ended up giving me some of their old hardware to try to understand the concept of ASIC mining and help me get my feet wet.

The issue was, they couldn’t find their Raspberry Pi controller. I have seen online where you can turn your personal Raspberry Pi 3 or below into a controller but I have not found how to do that. Any online tutorial links me to a broken link in Cannan. I have a Raspberry Pi 3b+ that I am able to use for this. Am I still able to accomplish this or do I have to sucker up the money to try and find a AvalonMiner model 7 control board somewhere? Thanks for the help.