A card edge connector assembly includes a card edge connector having a housing defining a card slot and holding contacts to electrically connect to a pluggable module and a host circuit board. The card edge connector assembly includes a guide cover having a main body including a first side wall between first and second end walls. The main body defines a center cavity receiving the housing and the pluggable module. The guide cover has a first alignment channel between the center cavity and the first end wall and a second alignment channel between the center cavity and the second end wall. The alignment channels are configured to receive alignment posts of the pluggable module prior to the card slot receiving the pluggable module.