Caster and camber are not adjustable on the MG Midget front suspension. The only adjustment is for toe.
In most cases excessive camber is caused by worn suspension bushings either in the upper trunion or the inner lower A frame mounts. Wear in the lower trunions can affect it a bit, but usually very little as these are not rubber bushed and even if worn don't move much laterally. Both of those locations originally used rubber bushings that wear or soften quickly and allow the suspension to move and produce more negative camber. I highly recommend replacing those bushings with either new ones or preferably new polyurethane bushings before checking the camber or toe. I'm not sure what the original factory specs are for camber or caster since they were not adjustable, but I check the camber on my car using a flat piece of steel bar stock that will span the wheel bead area on the wheel rim and a magnetic angle gauge I bought from Harbor Freight. http://www.harborfreight.com/digital-angle-gauge-95998.html If the camber is more than about 1.5 degrees negative, (top of tire leans in) and the bushings are new then I'd suspect some frame damage or wear in the shocks. The camber on my car is around 2.5 negative but except for uneven tire wear on the front it still handles and drives well. With smaller tires (I have 205s on 7" wide rims) the wear wouldn't be nearly as pronounced and probalby not a problem at all.
'73 Midget (V6)
'59 MGA (I6) under construction
'73 Lotus Europa
'52 MG TD kit car body project.
'98 Jag XK8
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