Need help on harmonic balancer removal

I need to replace the cracked and leaking harmonic balancer on my Detroit diesels 471s any ideas on how to get this thing off?
No disrespect CR, just looking for more ideas….
Including yours.
It’s been soaking in penetrating oil for three or four weeks.
I have used a air impact gun on it.
I’ve tapped the back of the boat on the puller with a hammer.
No luck yet.
I also put some heat to it , on the front MAP gas…

Look over the drawing again .
The “cones” are tapered , opposing tappers . Rear and front cone make a tapper sandwich. When the cam bolt is tightened down it pushes the pulley hub against the front cone , tightening down on the entire assembly against the rear cone tapper.

Reached out to another older J and T guy today, he told me will never come off pulling it like in my photos. That just tightens it more.
Need to tap the hub around in a circle, firmly directly towards the block , knock-er-loose ! Or loose knockers ! Which ever comes first!

Then the front cone will come loose. Fish it out with a screwdriver at the split in the cone .
Then slide everything off.
Plan to leave the rear cone in and alone.

That’s tomorrow plan. Will see .
I’m hopeful.
Been putting a lot of muscle on it the other way. Something not right .
Change of direction, giving what I see and hear should work.
Pulley came right off with a pulley puller , very little muscle…

And for some reason my stuff is backwards , compared to the drawing.
Hub bolt heads are facing the block.

What ? That’s it?
You saw the crack in the **** this 1000 miles way via computer photo!
Lol
You were right. I didn’t see it a foot away .
Any way, both cones have a full length split in them. “I. E. “ Tapper bushing .
The more you crank down on it . The more it tightens .
It’s opposing tapper “ cone “ bushings…

Got it off.
I resorted to carefully drilling out in pieces the front cone and tapping them out.
Then used my puller to get it off.
CR from all the photos i’ve seen including my Detroit diesel service manual shows the hex bolts facing on the front Hub seems to be installed backwards for some reason ?
Anyway the hub is tappers both sides with approximately 1/2” flat spot in middle.

I’m getting all new parts .
I am not replacing the rear cone…
Nothing is leaking there, oil seal is good.
Huge production for me to do that.

photo of front side;

Back size;

J & T MT. Laurel NJ getting me the parts. Cleaned it up real well with acetone and rags. Found the MFG, model, and DD part numbers stamped on the back side of damper. It's an Original (my guess), 1979( year on my block) Houdaille Torsional Vibration Damper light viscous one piece, DD part no. 5177763 for the 471 only. Now made by Vibratech TVD Springville NY. Looking at the website they make dampers for all the DD motors and many other motor Mfgs.

My parts drawing above is just a ''generic'' J & T drawing told to me by J & T, BUT, the part numbers are good for my 471. I'm quite sure the cones and hub are the same size for all the 71 series in the drawing.

Got the new harmonic balancer, new hub assembly, and front cone which was chrome plated ! Lol. The ONLY chrome “jazzy” thing on my motors .
Now I’m in the big time .
I’ll be sure to keep it ( cone) clean!

Painted up the hub and balancer, installed last weekend.
Ran the boat briefly while I had the belts off to the raw water pump.
Much improved. Not 100%, around 8o% better. Will work on it further in the spring .