I haven’t used or even seen the Showcars kit so nothing to add there. I have seen the Janek factory equivalent on a finished car and it looked great. Mine is all steel and it was expensive. Lots of steel parts available today and even reproduction aluminum wings. I would only use fiberglass if something else wasn’t available. These things are expensive so hopefully the budget is large.
List says steel and fiberglass parts list...every actual part listed is fiberglass. Page also says we need originals to make or improve molds lol, and more coming soon. Page hasn't been updated in eight plus years.
Showcars kit is paper thin fiberglass junk,don't waste your time or money on any of it. The Janak stuff is far better quality, but stuff like zee bars,headlight buckets and pivots, and latch tray assembly need to be steel for strength,durability and longevity. I prefer a cast aluminum wing too.