Snap a marker into each Fix, then position the second panel and press firmly. The marker points will leave indents in the panel surface, which can be used as pilot guides for the Buttons.
Button Fix Type 1 Metal Fix Bracket Fixing with Stainless Steel Retaining Spring
Button Fix Type 1 Bracket - Flush - Type 2 - Panel Connecting Fixings
10x Button Fix Type 1 Flush Bracket Marker Guide Kit Connecting Parallel Panels
Button Fix Type 1 Flush Bracket Marker Guide Kit Connecting Parallel Panels
24x Button Fix Type 1 Flush Bracket Marker Guide for Connecting Parallel Panels
Button Fix Type 1 Bracket - Panel Connecting Hidden Fixings - (Pair)