Board fit and routing on the 2.54 mm grid
The 640452-8: At 8 positions single-row, the header occupies about 0.800" of board edge, leaving room for adjacent connectors or passives. The board layout should include a keep-out zone around the pins to avoid accidental shorts.
Tin contacts and current handling
The mating face is tin-plated, not gold. If the application cycles the connector hundreds of times, gold would be the better choice; tin frets and builds oxide after repeated wipe. For a typical 22-24 AWG wire in the MTA-100 system, expect around 5 A per circuit at 30°C rise, but always check the terminal datasheet for the exact derating.