I've ran into some serious anti-lift anti-spacer people, that think it isn't safe. Of course these are the same people that buy consumer reports plastic POS imports... That being said, you can do what I did and do everything backwards
Skid plates, lighting, storage. recovery gear, communication equipment, all while I use and abuse my current suspension and tires. Once they wear out...time for a lift!
Personally for me, my parents were thrilled I was tearing apart my vehicle, learning everything about it, and buying me the tools and so forth. As far as professional installers go... my brush guard was professionally installed. When I took it off to put on MDB's radiator skid, I discovered they hadn't put all the bolts on, so it was bending part of the frame everytime it tapped anything. It's now mounted properly and reinforced with MDB's skid. Someday I'll cut it and weld it to a steel bumper
For most dirt roads, all you really need is MDB's radiator skid and oil pan skid, with and All-terrain tire. Helps to build up some handling on some dirt roads as well. And parents can't argue with the added safety those three add.
With any luck, your parents will see you adding the skids, and get bitten by the mod bug as well!
The problem with the Trailblazer is, people think you know what you're doing.