Eguller that would be the ticket, although done before by Maltby with the M series where they had different hosels that were interchangeable and needed to be epoxied in and the dynacraft spot putter which I believe had different necks that were bolted in. And I think the dynacraft had the ability to move the hosel more towards the heel and closer to the center, with more than one hole to screw the hosel in.
The above pic appears to be a fixed hosel or welded but of course looks can be deceiving.
The nice thing about the M series is they had several different putter designs AND several different hosel/neck designs, ALL interchangeable, but from memory it felt like shit as the center of the topline was hollow and that's where it was epoxied in. The finish was purdy, like a light bronze color.
I never tried the Spot, but easier adjustment then the M series, and I suspect felt better but ?? If you could somehow combine the two...might have a winner!