Multi-nozzle piping rig? I need to frost a ton of cupcakes (hundreds) for an event in a few months and I'm looking for something to help me do this. Has anyone ever seen a manual multi-nozzle (like 3 or 4-nozzle) piping gun, or something like that? (Imagine 3 or 4 caulking guns side-by-side.)

This project is too big for a home kitchen and yet too small for large-scale commercial production. I only need this a couple times a year, so it's not worth buying a professional automatic frosting machine. Would it be possible to rent one or run some batches in a commercial production-line bakery? How could I find one? (I must not be searching for the right keywords b/c I couldn't find any online near LA/Orange County).

I'm even willing to make a DIY project out of this but don't know where to start - wood, PVC, duct tape + baling wire?

Any suggestions? Thanks!

UPDATE: The objective is to decorate 3-4 cupcakes at a time while keeping the piping tips handheld in order to allow for the finesse of hand piping. By multi-nozzle, I mean more like this or this rather than this. Only one frosting, no conveyor belt, and not this EZfrost gizmo. Almost thinking a 1:1 pantograph, but to output 3 or 4 finished products at a time. The nozzles could even be hoses coming from a single tube/tank to a bracket with 3-4 tips, remotely kinda sorta like this.

The mechanism could use piping bags or these fillable caulking tubes, just need to make sure they're food safe. And for the nozzle tips, it would need to accept either a standard large decorating tip coupler, or allow me to put the decorating tip on and secure it somehow.

OH, and I have access to a 3D printer! (I just don't know how to create the models.)

For a commercial kitchen, I'm willing to buy ingredients and do all the production there to preserve sanitation. For additional human labor, I had friends and family help me last year, and 26 hours later they all pretty much said they never want to see or hear about another cupcake again in their life... not sure I want to do that to them again.
Food safe zip ties do exist. A thin rolling pin or knife steel could make a handle crossbar for a couple of piping guns, and palette knives or narrow cutting boards could be useful as structural elements to cross-tie the piping guns too. Everything made out of food safe parts :)