Quick update:

For the last few days, i've been busy leveling inserts. For the arrow inserts i decided to try something different, instead of sanding them flat. When i did the inserts on Travel time, i found that with the clock arrow inserts, sanding the inserts weakened them, making it a real ordeal getting them level with the pf surface. So with this pf, after i had glued the arrow inserts in, i decided to try leveling them by spraying clear acrylic lacquer over the inserts then sanding the clear level with the pf surface. I knew this would be time consuming to do, requiring multiple coats and sanding between coats to get the the clear level, but i thought it was worth trying.

First thing i did was to cut out a cardboard stencil of the inserts shape for spraying the clear on, When glueing the inserts i actually deliberately allowed the insert to sit very slightly below the pf surface (since i use PVA woodglue for the inserts, it would be fairly easy for me to remove them if this idea didnt work).

I tried it on just one insert first before committing to doing them all. The 1st pic here shows the stencil and the clear being sprayed on (i sanded the inserts lightly with 400 grit prior to installing them and spraying). 2nd pic shows one of the inserts with the clear sprayed on and drying. When dry, i sanded the clear with 600 grit wet&dry and Windex, until level with the pf. of course i had to do this several times (spray more clear and sand) before i had it level. This actually worked well, well enough that i did the rest of the arrow inserts this way.

3rd pic shows the white, yellow and green arrow inserts leveled. after i had the four left hand side arrows levelled, i lightly sanded them and the surrounding PF surface with 800 grit wet&dry & Windex, and followed that with 1200 grit. Ideally a polish with some Novus would've been the next step, but i didnt have any on hand so i used some "Re-po Paint Doctor" car paint fine scratch removing polish, they came up a treat after this step (not yet done in these pics) and because this stuff contains wax, i followed this with a wipe over with Prepsol and cloth, so i wouldnt have any problems when doing the black around the inserts. Incidentally, when i sanded the inserts i made sure not to remove the black from the inserts, so as to make it easier later on to re-do the black around them.