Well, I'm impressed. Assonance, consonance, internal rhyme. A clear storyline. Some of this is even clever. You're doing quite well.
I've never written a poem that I consider a finished work. I will even go back and edit a published work,
if I see where it could be improved.
When I read a structured poem I accent the read where the stress should be in the line and I had no problem seeing the rhythm in this poem.
That doesn't mean that the meter is perfect and I see a couple spots where the eye stumbles.
In S1L2 & S2L2 the first foot, /Down with/when I pull this foot out of the line and look at it, I read down with a stronger stress.
In S2L8 platinum when I pull the second foot out of the line /tinum/ I read tin with a stronger stress.
Harmonics suck, just pluck amuck
Just play it pit-a-pat
I don't think "suck" is a good choice. I also don't think using "just" twice in these two lines works.
Personally, I woud simply change "Just" in L4 to "And".
In morgues they do belong;
This is an inversion. I use them on purpose sometimes for an archaic effect, but in a poem
like this it usually forces the line.
Smash your guitar on your armoire,
Using "your" twice in the line doesn't work for me. I would simply change the second "your" to "an", "oak", "old" something like that.
Other than that, I think this is fine.