Well, the transmission is located concentrically by your 110mm OD of the bearing retainer.
The 4 mounting bolts (7/16"-14 UNC here) are used to retain the trans to the bellhousing.
The 4 holes in the trans are clearance holes for the bolts. Most likely about .030 oversize.
Can't your machinist bore the hole in the BH first, offer up the trans to the bore, punch marks in the face of the BH using a pointed dowel? Then drill and tap the 4 holes. Could be metric or SAE.
I checked an old Mopar Performance chassis nanual but no luck.
Or....send a message to Jamie at Passon Performance. He'll have the bolt pattern and might share it.
The input shaft length is the same for a SB or /6. I put a 1965 A833, originally from a 273 Barracuda behind my 1964 225 using factory parts with no issues. Same trans for either application.
