Thanks for the comments guys, but it's all done and ready to be tested again, knowing the original threads were too shallow, I drilled them deeper and also used a different flux with the silver solder, the last job didn't appear to have flowed very well, hopefully this will work fine. The 8-40 screws have too big a head, so I used some 6-48 torx head ring screws this time, I didn't have any more of the low profile slotted screws I used before.
Tim
