Ray,
Welcome. You will find, here, friendly and, as in my case, sometimes wordy advice and comments.
During my first rebuild of my A10 (during 2003-2006) I had a set of Whitworth sockets and tried to do all of the spanner work with Imperial, metric and adjustable open-end wrenches. For the current build (brought on by an oil-starved big-end bearing) I treated myself to a cheap set of Whitorth combination wrenches, and am I glad. It has greatly reduced the fussing, quickened the work and goes easy on the nuts. One very useful spot to have a 1/4W was in fixing down the barrels. By having a good fit I was able to get a sure grip with the open end while tugging the box end with a fish scale to reach 12-13 ft. lbs. torque on these studs in aluminum (25 lb. on the scale because of the slightly less than 6" lever of the wrench). The 12 ft. lbs. is a figure I got from a torque calculator for 5/16-18 threads in aluminum.
You won't regret spending the money on Whitworth sockets and wrenches. You will want them for as long as you work on British classics. If you decide to give up the bike, you can sell the wrenches with it for enhanced value or separately for near what you paid. From my point of view, you don't need the expensive British-made versions unless you are starting out on a career in British classics or have more money than I know what to do with. Asian-made will likely serve you well.
Richard