SBC 383, Piston to Valve clearance

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I know I'm going to get a lot of crap over this but... I have an e-bay engine, SBC 383, that came in the Factory Five 33 Hot Rod I just bought. It has never been run, never fired. With all the lifter failures, I pulled the intake to see if it has a hyd roller or flat tappet, and it's a flat tappet so I'm replacing with a roller. It has Chinesium aluminum heads and I don't really want to fall down the rabbit hole of pulling them. Not looking for big horsepower. Spec sheets says 9.9:1 comp so there is a dome. I'm looking at a Howards Retro fit Advertised Duration 278/284, Lift .500/.510. Anyone think there might be any piston to valve issues or should these specs be fine. Spec sheets says it has a .495 in it now. I know it's pure speculation but I also know a lot of you guys have experience building these 383 strokers so maybe you would have a good idea if I'm in the safe zone or not. On my BBC & Brodix heads 10.2:1 I'm running .601 lift with no issues but I'm unfamiliar with lift limits on mouse motors. Here's the spec sheet that was provided.
Thanks and please be gentle with me... LOL