1 For our sill plate upgrade for the ’56, we looked to Pete’s Fabrication. This company makes all kinds of billet dress-up items for Tri-Fives, and these plates are just one of the offerings. They are made out of 6061 aluminum, feature a mirror-like polished finish, and come with either lines (shown) or lines with a Bow Tie. They are larger than the stock pieces but still fit in the stock location and even screw down in the factory holes. These plates are about 60 bucks more than a stock replacement set, which is well worth the added protection and cool factor.