We had the Allon White conversion on our 1985 4/4 around 12/13 years ago and were very pleased with it - we traded the car into AW in Dec-13 so cannot comment on longevity. A chum has recently had an AW conversion done on his 1985 4/4 and it looks very good - he is very pleased.
Another chum has the Simmonds Dicky-Coupe conversion on a 4/4 4 seater and is very pleased.
In your shoes, I would speak to both and ask for a price. The conversation and the price could make your decision an easy one.
