To answer the original question: stock mini-quad headlights are not as bright as the 9005/9006 bulbs in a clean/clear composite housing.
If the composite housing is dulled/yellowed, then they are just as bad as the mini-quad units.
Physical they will bolt on w/o any mods, but will need the pigtails changed as they specific to the mini-quad units.
As stated above, if you get the units from LMC, then no changes to the wiring as they use the 9005/9006 bulbs. Which in turn are now brighter than the composite units. Glass vs plastic.
When a mini-quad dies, you replace the glass structure as it doesn't have a replaceable bulb. W/ the composite or the LMC, you replace just the bulb.
HD harness is only needed if you are going to use brighter bulbs.
W/ the mini-quad style lights, the 1st Chevy & both GMC style grilles require zero mods. Plug & play.
But w/ 2nd style Chevy grille requires slight mod to the light housing as the backside of the upper amber reflector is slightly larger & wont clear it.
I am running the 89 mini-quad units on a 99 Suburban w/ a modified 99 Escalade headlight harness w/ a diesel bumper, 00 Z71 pushbar & foglights.
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