Hi guys and thanks for the comments and suggestions. My MGB is just painted, and it was done 32 years ago as part of a body off restoration, and its still good, but being open topped it only gets used in clement weather. The R4 having a tin top offers wider scope, but would not get used in snowy/icy/salty weather.
The underside is completely clean. There is some paint, but coming from somewhere near carcasson, it has never seen bad weather, and there is just some mechanical abrasion. I have not got a pit, have some wheel jacks, so the method needs to be simple, and achieveable for a 70 year old. If I was doing a body off restoration then the paint and all the protective coats would be the way I would go. But starting from here, where the car has an amazing patina which I would like to retain, I do not want to disassemble the car, and I am leaning towards the dynax wax. I understand the comments about thin verses thick and heavy. We all have seen cars where there is something bullit proof under there and then a bit is missing and you can see that most of it is 2mm away from the metal with water behind. So if you use the Dynax, how do you stop a build up making a thick coat. Does it evaporate at time extends, and then you just do a quick top up spray? Do you spray into the cap and paint the areas that need precision with a small brush?