When I was making my alignment tool for the timing cover out the hub portion of one of my spare balancers, I used a brake cylinder hone to gain the slip fit needed to make use of the hub as a tool. So using a hone is certainly one way to gain the clearance and it did not take long to hone it out.
As for making a 235 or 261 balancer a slip fit retained by a bolt, I am not so sure. I have no empirical evidence but I would worry that just a bolt retention would heighten the possibility of even a slight loosening of the bolt, would then allow the balancer to work back and forth and create all kinds of havoc long term.
On the other hand, when I rebuild a 235 or 261, its SOP to have the crank snout drilled and tapped for a balancer bolt. I also have a fixture for drilling and tapping a crank snout with the motor together. I got mine from Mr. Hot Rod 6, but Tom Lowe at 12bolt.com also has a version.
https://mrhotrod6.myshopify.com/pro...-tap-fixture-tool-kit?variant=1142530609https://www.12bolt.com/store/p164/C...83-327-250-235-261-230-215-194-Tool.htmlFor context, I recently won the street tire drag racing class at the Trifive Nationals in Bowling Green Kentucky this past August. In the ten years that that show has occurred, I was the only inline 6 powered vehicle to run in competition and the only inline 6 powered vehicle to ever win a class at that show and race, in the entire ten years. I buzzed my 261 to 5800 rpm, once or twice to 6000 rpm, and at the end of each day drove back to the hotel, lol. Standard press on balancer, drilled snout and small block chevy bolt and washer. I did my usual post racing check when I got home to Pennsylvania, including checking the balancer bolt, and not a bit of movement or looseness after about 15 runs over that week, and driving all over creation in Bowling Green.
To my way of thinking, you need both the press fit and the bolt to really make sure the balancer stays put. That and by drilling and tapping the snout for a bolt, you can use a standard balancer installer to install the balancer, instead of a hammer and block of wood, and have really good confidence that you have pressed the balancer right up against the crank gear as required, instead of administering a few extra blows of the hammer to make sure you are.
Sometimes easy is good.
