Guys, I agree that boring the stem may not be ideal. I spent a while looking for a 1 1/4" stem of appropriate length and angle, non were found as of yet. I'll keep an eye open for one.
In regards to boring this stem I used, it was resized from a 28.6 to a 29.8 mm ID., which removed .6mm (.0236") from the wall thickness. In the major support areas this was about 10% of the available wall thickness, in the reduced areas it was closer to 15%. I plan to keep an eye, and eddy current inspection on it.
I'm still optimistic, a non adjustable 1 1/4 stem will Ebay for me to find. Just a waiting game being careful while we wait.
PK