Red inserts glued back into the playfield.
As suggested I used Super glue Gel.
Before I glued, I used a small brush with black acrylic around the top of each insert hole on the playfield. This was to reduce the likely hood of the timber showing bare.
Applied the gel to the playfield ONLY, and gently tapped the inserts into the playfield. Wow the glue went off really fast and left little time to adjust.
Overall, I'm pretty happy, some are better than others, my advice is LESS is MORE. To much glue and it comes out the top of the playfield and adheres to everything.
The picture was taken after a clean and polish, a little residue it evident around the inserts.
Re-populate started of the playfield. This is a complete jigsaw puzzle as I did not strip this field - if you see something out of place, please do not hesitate to tell me -thanks