The term "variant" is commonly used to refer to a car which may be substantially different but would incorporated some major components of the original model. This might be same factory production of a differnet model. It could be a different manufacturer using the same engine or chassis parts. It could be someone using a complete running chassis with a different body type. With a little stretch of imagination it might just be the same engine used for an application that doesn't even have wheels.

I will use a very broad stroke here to include anything mechanically related to the MGA which is not a standard production MGA Roadster or Coupe. This is just a way to index all things somewhat odd or unusual. This will not be an all encompassing description of everything, but rather a cursory list to let you know what exists in the world of "special" MGA.

VT-101 - FACTORY PROTOTYPES
VT-101_EX175 - Works Competition EX-175
VT-101C - MGA Coupe Prototype (Originally EX-197)
VT-101D - Experimental MGA -(0.8-MB pdf) -(history)
VT-101H - MGA Sport Coupe Prototype

VT-102 - FACTORY PRODUCTION VARIANTS (MG ZB Magnette and MGB)

VT-103 - NON-MG PRODUCTION VARIANTS

Nash Metropolitan

VT-103B - Buckler
VT-103D - Datsun 1000
VT-103H - Healey Sportboat
VT-103K - Karmann MG
VT-103M - Metropolitan
VT-103T - BMC Leyland Tractor

VT-104 - WORKS COMPETITION CARS
    TS-107-596 - 1958 Twin Cam Rally Coupe, RMO 101 - (Twin Cam section)
    TC107-629S - Aluminum body Roadster Converted to Fastback Coupe, SRX 210
    TC-107_1626 - 1959 Europe rally, So.Africa race 1762cc - (Twin Cam section)
VT-104_EX179 - The first factory "MGA" competition car, EX-179
VT-104_MBL - Rally Car MBL867, Nancy Mitchell and Pat Faichney
VT-104_EX181 - Supercharged Twin Cam factory land speed record car, EX-181
VT-104_EX182 - "Special Parts for Series M.G.A. for Le Mans 1955", EX-182
VT-104_EX182/38 - Car #64, 1955 Le Mans, EX182/38
VT-104_EX186 - Twin Cam factory race car, never saw competition, EX186
VT-104A - Works Development MGA Coupe, PRX 14

SRX 210

VT-104C - 1956 Sebring MGA Cars
VT-104D - 1957 Sebring MGA Cars
VT-104E - 1959 Sebring MGA Cars
VT-104F - 1960 Sebring MGA Cars
    TC-105 - 1960 Sebring MGA Cars
    TC-105_2571 - 1960 Sebring MGA Car #40
    TC-105_2572 - 1960 Sebring MGA Car #P
    TC-105_2573 - 1960 Sebring MGA Car 38
    TC-105_2574 - 1960 (Sebring) MGA Canadian Car
    TC-105_2575 - 1960 Sebring MGA Car 39

Sebring 1960

VT-104G - 1961 Sebring MGA Cars
VT-104G2 - 1961 Sebring MGA Race Engine
VT-104H - 1962 Sebring MGA Cars
    TC-109-104428 - 1961 Rally Deluxe Coupe, YRX986
    TC-109-104429 - 1961 Rally Deluxe Coupe, 151ABL

VT-105 - SPECIAL NOTABLE MGAs
VT-105A - First MGA Out of the Factory, HDC43-10106
VT-105P - MGA Police Cars

Jamaican

VT-106 - SPECIAL BODIES ON MGA CHASSIS
VT-106A - Fiberfab Jamaican, Late 1960's
VT-106B - La-Dawri, 1961
VT-106C - Microplas Mistral
VT-106D1 - Panelcraft Twin Cam, Autocar 1960

Stephenson/Panelcraft

VT-106D2 - Panelcraft Twin Cam, R&T 1960
VT-106D3 - Panelcraft Twin Cam, Destiny
VT-106E - Buyers CR90
VT-106F - Tornado Typhoon
VT-106G - Fiberfab Banshee or Caribee
VT-106H - Vantage Motorsports MGA
VT-106H0 - Vantage Motorsports, SCI 1990
VT-106H1 - Vantage Motorsports, KCI 1991

Devin - (off site)

VT-106H2 - Vantage Motorsports, KC 1992
VT-106I - Ferrari Testarossa
VT-106J - Ambro
VT-106K - Buchanan
VT-106L - Ashley 1172
VT-106M - Devin

Superamerica

VT-107 - MODIFIED FOR STREET USE
VT-107A - MGA 2+2's
VT-107B - "Bizarro"
VT-107C - Boat Tail MGA
VT-107D - V12 Jaguar MGA
VT-107E - Superamerica
VT-107F - Drop Head Coupe
VT-107G - MG Awan

Fastback Special

VT-107G2 - MG Awan (more)
VT-107H - MG Awan 2 Twin Cam
VT-107J - Hybrid MGA Coupe Special with Twin Cam
VT-107L - LaSalle style
VT-107P - Peel 1000 - Porsche 356 wanna be?
VT-107R - Roll-Up Roadster

W-I-D-E  MGA

VT-108 - MODIFIED FOR RACING
VT-108A - MGA-Judson 1960
VT-108B - "Hawk" MGA Fastback
VT-108C - Center Steering
VT-108D - Dragsters
VT-108E - Farrari MGA
VT-108F - Nedelko MG Special, open wheel single seat
COMP-160 - MGA record attempts at Bonneville Salt Flats

JEEP-MGA

VT-109 - MONSTER MGAs
VT-109C1 - Monster CHEVELLE-MGA
VT-109N1 - Monster NISSAN-MGA
VT-109J1 - Monster JEEP-MGA
VT-109R1 - Monster RANGER-MGA
VT-109W1 - Monster WHEELHORSE-MGA