I've put a lot of engines together and the band clamp works quick and easy if its sized right.
Like this one... Tho the wrong size, they ratchet and lock. https://www.summitracing.com/parts/oes-25037
There is no value in freezing the piston when its the rings keeping it from seating. Same is true of more oil. When the rings are properly collapsed, the piston will drop in. On that note, did you drop the new rings in the cylinder (Top and 2nd ring)? If YOU DID NOT, DO IT NOW before going further. If they are oversize for some reason this would explain a lot.
Put them in on edge and rotate them flat and use a piston to square them in the bore. Do SO AT THE TOP AND BOTTOM and measure the end gap and make certain it has some freedom to expand (an open gap per spec).
Also, how did you index the rings? Normally there is a specific pattern for the top, 2nd and oil rings orientation. Sometimes its a simple as 120 degrees apart but do NOT align the top ring with the exhaust port.
As for the scratch in the wall I would leave it. New rings seating in may be enough to take it out but its not worth opening up the whole cylinder from top to bottom 360 degrees for that. You'll loose more ring tension and open the ring gaps up for something that isn't hurting anything.
Good luck. And DO fit those new and old rings in the bore and measure the gap. This is MUST! If off, it could ruin the block!
Like this one... Tho the wrong size, they ratchet and lock. https://www.summitracing.com/parts/oes-25037
There is no value in freezing the piston when its the rings keeping it from seating. Same is true of more oil. When the rings are properly collapsed, the piston will drop in. On that note, did you drop the new rings in the cylinder (Top and 2nd ring)? If YOU DID NOT, DO IT NOW before going further. If they are oversize for some reason this would explain a lot.
Put them in on edge and rotate them flat and use a piston to square them in the bore. Do SO AT THE TOP AND BOTTOM and measure the end gap and make certain it has some freedom to expand (an open gap per spec).
Also, how did you index the rings? Normally there is a specific pattern for the top, 2nd and oil rings orientation. Sometimes its a simple as 120 degrees apart but do NOT align the top ring with the exhaust port.
As for the scratch in the wall I would leave it. New rings seating in may be enough to take it out but its not worth opening up the whole cylinder from top to bottom 360 degrees for that. You'll loose more ring tension and open the ring gaps up for something that isn't hurting anything.
Good luck. And DO fit those new and old rings in the bore and measure the gap. This is MUST! If off, it could ruin the block!