The Clapping song is still making great progress. For drums I decided to use the drum kit from the SNES Street Fighter II as opposed to the Earthbound one (originally I used CPS1 SF2 samples that I got thanks to Audacity's Import Raw Data function). For vocals, I decided to switch from Vocaloid to WPTTS, because it's better at handling talking and singing parts at the same time from my experience, since I could just switch the voicing mode parameter from normal to sing, and back again in a few verses. For the preset voice, I decided to use Milktoast because to me, he sounds more like Barney to me, anyway, though if I have to tweak a few formants, I'll do that.
As for the other song you mentioned, I am still looking for a backing track for said song, and if I can't find it, I'll just make my own, since I have a Sunsoft 5B instrumental that I am working on with Famitracker in case I can't find one.