...Let's stay with the Topic and Not Rant-On. That's why I started a Dedicated Thread. Thanks.
You seem to be 'Back-Peddling' on Your Idea. Perform your work and post some pictures, keep us posted. I will tell You, you will need a 25 Ton Press. I have a 10 Ton and I don't think that will do the Job, by Experience. Last, If you do Not CORRECTLY Support/Back-Up the Aluminum Casting, You WILL Break It!
As a Machinist, if It doesn't Fit, I Will MAKE it Fit!! I'm NOT going to Move any Engine BACK, and Spoil the PMOI!!
I'm actually 'Hoping' the 'Flat' Pulley is Wrong! I will use it as a 'Comparator' to Machine My Own, 40 Degree, Included Angle for V-Belt. And I can Make it Smaller (4.9") as the 'Over-Drive' Pulley You now see Mounted. Maintaining the Max. Overdrive.
I have worked in wood, also! I have Created Dozens of projects, Exclusively in 'Old Growth Black Walnut', 'CoCo-BoLo', and My Favorite, 'Sonoran Desert Ironwood', add 'Honduran/Nicaraguan Rosewood'. I work Only with Precious woods, it makes the Project More Valuable and Most Unique.
You would not believe what I have Created!
Now, Back on Topic.