Boring out the Housing, isnt just that. its not a "bore" its an entire new profile for the new wheel. Not only do you have to have the housing machined for the profile for the 57trim wheel, the back side of the wheel it self has to be machined of the profile of the stock wheel, and then reemed to shaft size. On top of that the center housing has to be machined bigger to accept the larger exducer of the 57 trim wheel. a lot of machining, and time goes into these, and if the wheel isnt perfectly machined, youre just asking for trouble.
The price fore a machined 57 trim housing, wheel, and center housing would be like $400, migh as well pay the extra to get it balanced, cleaned, rebuilt at the same time.
id beg to differ.