Out of kindness to the Boring head, I would feel inclined to make or buy a Flycutter. It will always "Come in handy, one day" for other jobs.
And is likely to be more rigid than a boring head, when subjected to interrupted cuts.
MIke Cox published a design, in MEW, for a Flycutter on the principle of the Tangential Turning Tool.
Although mine differs slightly from his design, it functions quite well!
Howard