Good point. Remove the trans, then the tin inspection cover under the BH and the clutch disk and TH bearing should fall out. Or, remove the cover and get hit in the face...
Oddly, I have 2 vehicles w/ the old iron BH and starter that bolts to the BH. Oddly, those starters might be bigger than normal and never have the supposed heatstroke problem.
Check to see if the big hole in the back of the BH is the same size as the bearing retainer diameter of the trans.