As regards exit door limits, 4 main doors and one overwing exit each side meant a maximum of 149 seats (and still does). When Monarch bought Boeing 720Bs from Northwest with this layout, they had them modified at Boeing Wichita with an extra overwing exit each side (as on the 707 and which had always been an option, rarely specified, on the 720). This meant they could put as many seats as they could fit in up to the legal maximum for this layout of 189.