My hole blocking method was a success 
got the holes cleared out and cleaned up, was a bit of a mission cos the basalt was quite furry where I drilled open the holes, so I had to clean up each hole with a surgical blade.
For those playing at home, I used a small drill bit from the unskinned side of the deck and drilled through the center of the inserts so that I could locate the holes to drill on the skinned side.
Then I used a trick that I like for drilling/enlarging holes in fibreglass enclosures… you run the drill bit backwards. When you run it forwards, it almost always wants to grab and fucking tear through the fibreglass. If you run it backwards it just goes through nice and smooth.
This worked really well as the backwards running bit didn’t want to eat the wood, so it centered itself, and when it did pop thru and hit the insert, it didn’t do any damage.
Plugged up all the holes again and ready for skinning the top! Not sure when I’m gonna have the time to do this… hopefully Wednesday arvo.
Stomp pads are coming out nicely. Although i fucked up which way up I printed the pieces 
no matter, will be covered by grip tape anyway.
I was hoping to pick up some 6 core cable to use for the sensor extensions to the center of the board… 28awg is fine for sensors right? This is the shit i wanna use Shielded 6 Core Cable 28/0.12 - Maker Store PTY LTD