Yep, I believe it is zinc. The kit from Eastwood comes with the necessary things to make it work. Chemical, zinc strip, batteries, etc. I have always used a 1.5 lantern battery but this time around I used a small power supply that had a 5 amp capacity. I adjusted the voltage to 1.6 and amperage was 4-5 amps at start but quickly dropped to about 3 then down to nearly nothing as the plating was done, about 10 minutes for the larger parts.
It worked great on the trunk lid support. If I had painted it, the paint would have just been rubbed off at the joints and not even been able to paint all of it.
You would have no problem with the carb parts you are asking about.
I do any filing, sanding or grinding first then follow up with bead blasting which makes the part uniformally velvet texture and clean. Follow this up with a hot water, soap and a light degreaser and you are ready to go. Don't touch the piece before plating and any dirt or rust will show after plating.
Hope this helps and good luck.
Fourdy