Hi there,
This is a pretty straightforward conversion, if a trifle expensive these days.
You will need a lot of hardware including the later stub axles and hubs , plus the discs, calipers, pads etc.
Most of these parts are specific to Morgans so you may not have much luck finding anything else to fit.
However whilst the parts above will take care of the front end , I would really strongly recommend using Aeroquip front brake hoses, and a new master cylinder in order to cope with higher braking power.
I am not sure if 1952 is a year when MMC fitted narrow drums to the +4, if it yours has these , then a much cheaper upgrade can be dome using the wider (full width) drums from the later cars (plus of course new shoes, and possibly new wheel cylinders). I think these can also use the same stub axles (but please check with others first. Unless you are into repeated high speed stops and use in deep water I would think that this conversion will give you the braking power you are after , but at a fraction of the cost of the disc brake set up.
