I epoxied 2 hinge blocks to 2 end ribs last night and found the blocks had moved slightly when checking this morning some 12 hours later. A sharp tap with the hammer and they broke free (along with some timber so I know the T88 is doing its job). Sanded smooth to remove the dried epoxy and then rough sanding again for a good gripping surface, this time as well as the elastic bands I also pushed some 1/4" bolts partially through to hold the correct position. After a few hours I will remove the bolts so they are not fully glued in and then allow things to cure for a full 24 hours. Ran a 1/4 drill through afterwards to clean out the holes and then lined them up with the plywood supports and outer hinge blocks. Clamped tightly and drilled right the way through.