I did have to oil my injector O rings to get them into the holes. also, depending on the age and condition of your original rings they may have swelled up. Did anyone measure the hole size? How does it compare to the holes in the stock manifold. be Aware if using replacement O rings on the injectors that top and bottom ring are ever so slightly different size.

Are all the holes too small, or just 1 or 2? I run a machine shop, and when we finish a job the tools for that job get put in a box with the jigs, and become dedicated to that job/customer. Most shops work this way. It would be very unusual in most shops for the wrong reamer to get used for something like this, and if it did, likely that a whole bunch of pieces would get made the wrong size, not just 1.

John C.