doors and such are completly different.. so front seats about it...
X2! Several years ago, I found some nice boneyard Quantum front door panels, thinking I'd like those speaker enclosures & door pockets for one of my Dashers. Quick measurements showed that the Quantum door is quite a bit longer... damn.
Dasher console might work with minor mods. You'll tap your creativity to mount the Quantum's power window switches; personally I like to mount 2-3 rockers at the (almost vertical) rear surface of the Dasher console. Tight, but fairly unobtrusive & the switches pick up less accumulation of dirt, etc. than when mounted horizontally.
Actual instrument cluster insert is 'similar' from '78-on Dashers. '80/81 Dashers got clip-on speedometer connector like Quantum. Fuel gauge reading is a little off, but still usable.
Dasher shift knob fits my Quantum shifter!
Even when we could by them new, OG Dasher shift boots were crap; will probably buy or make a leather unit to work with the very short shifter in the D/D.
OTOH some Audi 4000 interior pieces may fit your Quantum nicely.