The brick wall I hit had nothing to do with the notch. At one point, there wasn't an option for a 130T flywheel with the notches so you could run EFI. I went round and round for awhile looking for fixes, including a dual pick-up distributor that ended up being vaporware, and trying to relocate the CPS to the front. I knew of one individual that was able to get a 143T flywheel cut down to fit a 130T ring, but others were told that was impossible and shops refused to do the machining. Red at McLeod (as I recall) even said it wasn't possible to build a flywheel that worked, while one other individual got a custom flywheel build that was hugely expensive.
And don't forget, it's not just the guys that wanted to put an EFI Magnum in front of an old school 4 speed that struggles. If you wanted a T56 instead, you were in the same boat because there wasn't a bellhousing that would fit the stock 143T flywheel and bolt up to a T56. That's why the one guy bit the bullet and spend a good chunk of dough on a custom flywheel, he wanted to bolt a T56 into his Dakota.
In the end, it's all water under the bridge now that you can buy a flywheel for a reasonable price.