First get a really good Torx set , impact if you can. Be4st to get a couple of the size you need as they are tough to get out. I put the bit in the bolt head with a 6" extension and gave each one a couple taps with a hammer before I took them out and all mine came out OK. I did break one bit in the process though.

As for the rotor cover on the right side of the engine. I haven't removed one yet. I did just as you described. Set the timing marks on the cams with the marks on the drive gear and the "Top" at the top. Don't move the engine while the cams are out just to be sure. Put back together with the new shims with the marks lined up again and you will be fine.

Don't forget to use the pins to hold the back lash gears. If the pins come out you need to re-tension them.

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