First off, welcome,Chris. Next, please accept my condolences. I'm very sorry to tell you that whatever you paid for those carburetors, you paid too much. There is not and there never was a 32 mm. PWK carburetor produced by Keihin. Three facts: The PWK is a dedicated 2-stroke carburetor. Keihin for some reason produced only one needle jet (AKA atomizer, AKA emulsion tube) for each venturi size in the PWK series. 2-stroke motors require needle jets that are much richer than a 4-stroke motor requires.
Years ago a hack at JRC Engineering in the USA had the bright idea of having cheap knockoffs of the PWK28 bored out to 32 mm. to get a smaller needle jet that would get closer to the requirements of British 4-stroke twins. The carbs were badly made and caused trouble, but a lot of them were sold because they were cheap and because guys didn't know enough to question JRC's very effective advertising.
Jerry Heiden and Mike Lalonde noticed that item and started selling the same thing. Because of outing by a few folks who knew the difference, Lalonde and Heiden started having the knockoffs made without the Keihin brand name. When enough complaints had been voiced about quality issues, they started using authentic Keihin PWK28s punched out to 32 mm.
But that did not resolve the underlying problem, which is that while the carbs can be tuned well enough to let a 4-stroke motor run, the needle jets are still too rich--and yes, they're still too rich for a 750 cc. 4-stroke motor with a free-breathing exhaust system, etc. Why does this matter? Because the NJ is the primary metering component in the cruising range of the throttle, and you would do very well to go 36 miles on 4 liters of fuel with bored out PWK28s. So here's the choice. Pay now for workable carburetors, or play with the PWKs and, if you're successful in making them work, pay later in fuel costs.
The use of genuine Keihin carbs put the price very close to the price of the Mikuni VM34, which can be tuned very effectively for our application, so Mike's XS and Heiden Tuning have both stopped selling the modified PWK28. Mike's has started selling VM34 kits, and I think Heiden has done the same.
If you want to have a go at tuning those carbs, mrriggs wrote a very detailed thread on the process a few years ago. Look around and you'll find it.