Gilder shot a 6-under-par 64 and Watson a 66 to reach 10-under 130 at The Moors Golf Club. Both are seeking their first win of the season.
Bobby Wadkins went out early and shot a 61, missing Isao Aoki's course record by a stroke. He was tied for third with five others, including first-round co-leaders Gil Morgan and Leonard Thompson, at 9-under 131.
Also at 131 were Larry Nelson, Vicente Fernandez of Argentina and Morris Hatalsky.