Your pistons look like Speed Pro's, but it would be hard to say for sure unless you can see a part number. Honestly, I don't know if I'd mess with them other than wiping the tops with a rag with some brake cleaner on it. Use a shop vac to clean each cylinder really well after you clean the deck surfaces to prep for the new head gaskets, just in case any debris might fall down into a cylinder. While the heads are off, it might be a good idea to run a stiff wire, like a coat hanger down the oil holes between cylinders 1 & 3, and then again on the hole 6 & 8. That will tell you if they are clear, so oil can get to the rockers. You could also spin the oil pump with a hex rod and shoot oil across both fenders.....lol. Clean all your head bolt holes and chase them with a tap if you have one, before you put the heads back on. Put a few drops of oil on the threads of each head bolt hole before you install them, so they will torque more accurately. Hopefully, the new heads will be a nice improvement!
:thumbsup: