First time engine build: Chevy 350

SouthArk370Z

Read up on how to clean and torque bolts before you go too far. When in doubt, use new fasteners.

As long as they are the same length, it won't be a problem. IIRC, the "ball end" rods are a little harder but that shouldn't make much difference unless you plan on pushing the engine hard. Personally, I'd go ahead and replace them all but, depending on what kind of condition they are in, that's probably overkill.
Get roller rockers if you can.

BTW, you can't tell if a cylinder has been bored 30-over or if push rods are the same length by looking at them. Invest in some good calipers and other measuring tools. You'll need at least one torque wrench when you start putting it back together.

Don't scrimp on your tools and take your time putting it back together. A properly assembled SBC will last a long time.

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