Looking great so far bud! Sorry if you have mentioned it but where did you source the 90spec trim from? I thought it was NLA?
Ive gone a slightly different route with mine now...new front seats are in but I'm already contemplating something else lol
In regards to your head unit issue, I would run a new cable to the battery and a new earth...If that doesnt help then I would say possibly something in the CD mech is shorting something if your saying the iPod works fine. Also had another issue with something similar where the MUTE cable was occasionally touching the head unit chassis and causing the head unit to mute so might be worthwhile checking that while the stereo is out
And one last thing, if you sell the Brembos, let me know what you are after for them, I might take them