Adding spacers to current lift

[15KSChevy]

A friend of mine is looking into 3.5 inch lift for there 2017 and was asking if they could add additional 1/2 inch spacer on-top of the 3.5 to get closer to a 4 inch front lift? I have herd of people adjusting there struts on lifts that include new cross members, knuckles diff drop ect..  but wanted to know how bad it would be on ball joint and such with say a the newer style fabtech, rough country, superlift 3.5 kits . Thanks for any help

[jimmyboy8301]

most/all of those 3.5" kits are garbage and net horrible front suspension angles, to then add another 1/2" spacer on top of that is like playing russian roulette with your suspension with 5 rounds instead of 1. 

[15KSChevy]

Thats what I was trying to explain to em, They ordered the rough country 3.5 knuckle lift as well as a set of control arms for 3-5 inch lifts. I tried to explain they would be better off for a few hundred more buying a ac 4 inch lift but didnt listen!