Wwyvern: I can confirm also having experience of a strong but misleading ADF beacon on crossing from Iran into Turkey on that CENTO Route circa 1967/8. A back-plotted 3-line fix put the source nicely across the then-Soviet border.
And for LordFH, that clean-up routine was a standard Flt Eng task on the C-141A before Top of Descent on any long route leg.