Its been years since I have seen one, back in the very early 70s, we had a small group of ford guys and one of them worked at the local ford dealer in the parts department, he had one with the manifold on his 70 boss 302 mustang , later he brought a spare engine shortblock for it, first thing you noticed it had four bolt mains and screw in core plugs, later found out the rods were the special 3/8 bolt 289 long rods , the boss Pistons only would fit with that combination, that is what made made me notice yours because of the top that comes off, did not know it was a bud more, on the pluss side it makes porting the intake to match the heads a dream, thank for reviving old memories from the past 😸