Sorry never updated this thing, now this tank is for sale and want to close this thread with some advice from my experience for anyone who may start a project like this down the road.... do it !!
1) use one single piece if possible.. the most difficult part was joining the seams on both sides, only joining one seam would have been much more simple.
2) the saltwater epoxy for attaching to corals DID NOT adhere to this bark, not sure why but it simply wouldn't.
3)use more silicone than you think is necessary... as the bark absorbs water it will expand, this expanding puts added stress on the silicone... in hindsight this is the one area where I could have made this project much easier on myself
Overall I absolutely recommend this as an overflow cover for anyone thinking of this, I'm sure many of my future tanks will have something similar, especially now that I know a little more about what I'm getting into
Thanks for looking and if anyone has any questions send me a pm and I will be glad to help.