Hi David....I really love the 350 platform....I did over 9 of them in the last year. I only had to replace one cylinder on all those and used a cheap aftermarket with great results for a 353. That said, there are two ways I would go with your project. My favorite would be to get the HyWay 353 piston and cylinder kit with the popup piston, do a gasket delete and a .023 or so squish. I take the adaptor block on the 350 and with a flat piece of plate steel, sand it down flat on the top to give me the squish I want....it also gives a flatter surface then stock to do the gasket delete. The saw I did this to using the stock cylinder with the HyWay popup using a 18 inch .325 chisel is very impressive and keeps up with my 61 Husky easily. My second choice would be to turn the 350 into a 346 hybrid by purchasing a stock OEM 346 top end, and do the same gasket delete and squish etc. I did this as well, but got a great deal ($29) on an aftermarket closed port top end for a 346 so went that route instead of OEM. The aftermarket top end performs well, but I haven't done a lot of cutting with it to really evaluate it, and can't tell it if it is as good as the OEM 346. Of the two I like the 353 with pop up better as it seems to have more torque at lower RPM. I just get cheap aftermarket mufflers, but make sure to get a 346 style muffler brace and modify it for the 350. Also use locktite on the muffler bolts. On my 353 with popup, I cut a slice in the right side of the muffler and tapped the inner side with a hammer and pryed the outer side out to make an opening for a cheap muffler mod. It may or may not add power, but it sure is LOUD. Have fun with your project. I've got 3 more 350's I'm going to attack next fall and will likely go with 353 kits. Also don't forget to replace the plastic carburetor clamp with a steel one. Barry