Small Bolt Pattern Wheels Don't Fit Wilwood Disc Conversion
There's these, pretty much identical to the set I just sold except with a 4" backspace. Center bore is 2.93", so, according to the Wilwood instructions you'd need to have them machined open to 3.050". And I would guess that they're for 7/16" lugs too, so, you'd need to change that as well. Since they're a conical seat you'd need to have them machined for the larger studs too if you were doing it right.
https://www.summitracing.com/parts/are-vna695769/overview/
And FYI, on the Summit Racing info page for that brake kit it lists the minimum hub bore as 3.050". I can't believe PST said they'd fit anything SBP and stock.
https://www.summitracing.com/parts/wil-140-11022/overview/year/1969/make/plymouth/model/barracuda
Honestly, I would get rid of that brake kit. Make PST take it back, they were
100% wrong about the wheels fitting, they're not even close. And it's not like they shouldn't have that information, Summit obviously does. I don't know what Wilwood was thinking when they designed that hub. That's a horrible hub design to have it be that large of a diameter, let alone to offer it with the SBP like that will help you. It's worse than the stock 73+ disks, and those already have a big register as far as aftermarket wheels are concerned. Not to mention the use of 1/2" studs. It wouldn't be easy to find wheels for that kit using the BBP that it's also drilled for, but at least then you'd have more options and the lugs would be the right size. To use the SBP on those hubs is a nightmare.