The MGA is built around a separate steel chassis with a body bolted on top, a fundamental architectural distinction from the monocoque MGB and Midget that followed. The chassis itself is a fully-boxed steel perimeter frame with side members swept outboard between the axles to allow a lower seating position, with a welded "goalpost" assembly providing rigidity at the scuttle. The body is all-steel except for the doors, bonnet and boot lid, which are aluminium-skinned with X-brace reinforcing frames, a wood stiffening batten and anti-drumming felt. Plywood was used for the toeboards, the four floorboards and the one-piece heelboard, all painted black.
Bodies were built by Morris Motors Bodies Branch at Coventry. This construction makes MGA bodywork restoration a more involved undertaking than on the later monocoque cars. Rust damage to a chassis rail requires welded-in steel repair; damage to the aluminium bonnet or boot lid requires different panel-beating skills from those used on the steel wings; and the two-piece assembly means the body can be lifted clear of the chassis for major work but must be re-aligned correctly on remounting.
Known MGA bodywork weaknesses
Sixty-plus years of service have taught MGA owners where the weaknesses lie. The centre chassis section, floorboard rails and battery cradles, is an early casualty on any neglected car. The chassis side members from goalpost to third tubular crossmember are another prone area, often hidden under undersealing. Stress cracks can appear at the top of the goalpost assembly and need professional welded repair.
The aluminium panels (bonnet, boot lid, doors) are prone to electrolytic corrosion where the aluminium skin meets the steel X-brace frame, particularly at fastener points. Sills and door pillar F-sections are structural members of the body; rust damage here affects shape retention and is one of the most common major MGA restoration jobs.
Variant-specific chassis and body differences
The MGA is not one model but five: the 1500 roadster and coupé (1955 to 1959), Twin Cam roadster and coupé (1958 to 1960), 1600 roadster and coupé (1959 to 1961), 1600 Mk II roadster and coupé (1961 to 1962), and the De Luxe variants with Twin Cam running gear in pushrod bodies. Twin Cam chassis is pre-drilled differently for oil cooler pipes and brake pipe routing; chassis numbers are typically three or four figures only (pushrod cars five or six). From chassis 66574 the front chassis extension was altered to accept the optional anti-roll bar. On 1600 Mk II from chassis 100352, seat belt anchorage points were incorporated.
The 1600 Mk II grille was substantially modified: the bars were pushed back at the bottom and an inner surround panel was added, giving a recessed appearance. Coupé bodies were introduced September 1956, sharing the roadster scuttle but with a modified front shroud, completely different doors (with swivelling front quarterlights, wind-down windows and external door handles, the roadster has no external handles, entry being via an interior pull cord).
Ordering by sub-category
The Bodywork section is divided into eight sub-categories. Bonnet & Fixings covers the aluminium bonnet and X-brace frame, hinges, prop stay, lock, safety catch and fasteners. Bootlid & Fixings covers the aluminium boot lid with hinges, lock, weatherstrip and badge hardware. Chassis and Fixings covers chassis side members, crossmembers, outriggers, repair sections and body-to-chassis fixings.
Doors & Fixings covers the aluminium-skinned doors (roadster and coupé differ significantly), hinges, locks, window mechanisms and internal hardware. Exterior Styling covers grille (1500/1600 and 1600 Mk II differ), badges, trim strips, wing piping and chrome details. Glazing covers windscreen glass (curved coupé differs from flatter roadster), sidescreens, quarterlights and wind-down windows. Panels covers front and rear wings, valance panels and sill repair sections.
Upgrades & Alternatives covers modern reproduction panels, chassis repair sections in thicker-gauge steel and other non-original options.
Ordering considerations
Body and chassis work on an MGA is typically a significant undertaking, a complete restoration involves lifting the body off the chassis, repairing both separately, and reuniting them. For owners approaching a major restoration, consulting the factory workshop manual and a specialist MGA body shop is recommended before ordering significant body panels, as panel-by-panel fitment can vary depending on the condition of adjacent structure.