help with engine number...and a few other question

Was going to sell my bike but I'm going to keep tinkering just in case it don't and who knows maybe if I can get it going right ill hang on to her. I bought some intake manifolds for my mikuni carbs and they were to small. Apparently I have a set of police bike carbs, or at least that's what they guy that sold them to me said. Anyway the title says its a 78 kz1000 a2a. The numbers I could read after using a pencil to shade the numbers because I couldn't tell by looking because of the previous owners paint job. From what the shade method looks like it says ZT00AE070775. Should have a k at the begining right? Any help would be nice. Money is limited and I can't keep wasting it. Bought the intake manifolds used and can't return them so I'm just up a brown creek on that deal and I'm still stuck with my old cracked air sucking manifolds. Is it the original motor with other carbs or wth is going on? Included pictures of the carbs to help identify them. Also does that vacuum set up look right and is that what goes to the petcock vacuum? It has three nipples. One fuel feed from the petcock to the carb is run, one is capped off, and a somewhat smaller nipple is just open. Fuel gets to the carbs some which way because I've rode it around the block. Also it has the two throttle cable set up but is only using one(currently unhooked so I can pull the carbs real quick with a screwdriver). Sorry for all the questions but I grew up around old panheads and this is a different world to me.