Pickup replacement issues

So my Wizard Pickups arrived...booootiful...

However, there are differences in the size of the pickup covers and specifically the mounting screw positions compared to the pickups that come with the kit. I was expecting this, but thought there would be sufficient leeway in the existing pickup cavities to cope...there isn't.

I took a look at the kit's pickups to see if I could remove the pickup covers and reuse them on the new Wizard pickups, but it seems not possible without damaging them - they are all enclosed and glued together.

Now the neck pickup is fine, because the cavity in the body is significantly larger than it needs to be. However, it wil not fit the existing pikcguard, so its a good job I will be cutting a new one anyway.

The bridge pickup is the main problem. The differences in size are minimal, we are talking maybe 2 or 3mm, but this means I need to work on the pickup cavity a bit. Given the small difference, I have sanded one side of each of the mounting points. This allows the new pickup to slide in but leaves an ugly gap on the other side.

My plan therefore is to use some wood glue and filler stuff and then sand down so there is no gap. As I am painting the guitar this will not matter, once completed you won't know I had to do this (I hope!)

This next photo is of the sanded cavity and marked in pencil is where I need to fill. Not sure how things will go getting the wood filler to stick there, seeing as it will be such a small piece - will have to wait and see I guess.

So, it is worth considering carefully any pickup replacement wth these kits. Due to this sort of issue, you may choose to get pickup surrounds to cover the wrong size or adjusted cavities - you could end up having to rout different cavities altogether depending on the pickups.