Massey 39 2 row planter

[Ky farmer16]

Just bought a massey 2 row planter don't k ow a whole lot about it but it came with the original fertilizer tubes and next row arms can anyone on here tell me about the fertilizer hopper it looks like to me there would be some sort of plate at the bottom you could adjust to let out as much or as little fertilizer as needed to be picked up by the auger and dispersed evenly and I cannot find anything about them anywhere on the internet so I didn't know if someone had one somewhere out there that could tell me about them or send me some pics or a diagram of it I'd like to get it up and going before spring so I can plant some corn....thanks in advance here are some pics of the one I just bought