Hi, these torques are from the XS1/2, but there shouldn't be any difference to the others. Overall, these are no sensitive values and the sequence of tightening is not important either. But it's important to put all the bolts in first before you start tightening them, otherwise the last ones might no longer fit, especially on the upper brackets!
Raymond recommends it exactly right: first insert the lower middle bolt only, then swing the motor forward and install the carbs before moving on to the rest of the bolts. This is the only situation in which you have this “luxury” of convenient carburettor installation