I have the 9-bolt clutch in my 1-ton. It has a 9-hole, 6V flywheel.
When I had it all apart a year ago last summer I went looking for a 6 hole flywheel, which, unless I found a 54 flywheel, meant changing the starter too. I ordered a flywheel listed for a 55-62 Chev I6 from Summit Racing. Rock Auto's listings were too confusing. What came in the shipment was for a V8. I sent it back and had my existing flywheel resurfaced. The machinist suggested that if I wanted the 6-bolt clutch, "Just redrill the flywheel for that clutch." I put the 9-bolt back in as it was in good shape. I'd had it rebuilt about 2 years before. All is well.
