In conjunction with the downsizing of the model line, the third-generation Marquis and the adoption of the Panther chassis transitioned towards increased parts commonality between Ford and Lincoln-Mercury full-size lines. Along with a common wheelbase (for the first time), the Marquis and the Ford LTD shared nearly their entire bodyshell; many non-visible components were shared with the Lincoln Continental/Town Car and Continental Mark VI. Distinguished primarily by trim, the LTD and Marquis shared a common roofline (the Marquis 4-door is distinguished by a full-length vinyl roof). The two-door hardtop and four-door pillared hardtop were replaced by sedans with fully framed door glass with fixed quarter glass in the rear side doors (each model had its own door design).