Symmetrical as far as I could tell, Its been a while since I installed it and the sides are sided as theres a little endcap bit thats asymmetric (you can see it on some of the pictures others have posted) but I don't recall any cut out.. There's join behind the screen but you can't see that, and that would be the same for left and right hand drive cars.
I just installed my Alcantara dash and am really thrilled! I traded my stock dash top for a covered one from RPM Tesla in California.
The dash top is super easy to R&R, it is simply snapped in place. Not sure how easy it would be to cover it yourself. I didn't make a careful enough comparison to be sure, but it looks like the woodgrain portion is heat staked to the dash cap base. I think that RPM ground/broke/melted the staking to remove the woodgrain part, covered it, and then re-staked the covered woodgrain part. Probably tedious but I would not be afraid to do it if I had time. Finding matching Alcantara is a whole other subject.
Whatever method you choose I'm sure you will be pleased with the result.
* Note this is the for the dashboard only- we have a separate listing for dash & door trims on cars built on/after March 2021 * Transform the interior of your Model 3 with these dashboards which are trimmed in genuine dark grey alcantara material to colour match the door trim inserts on the...