@JohnH89 Thanks for the advice on the capacitors. Some of the capacitors were £10-£11 which sounded insane money. I decided not to mess too much with the bass before Sat.
However one of the advantages of a modular bass is that I can change the pickups around quite quickly. I created a new pickguard design for jazz type pickups, printed it out, took the old pickguard off and the split pickups and put the bridge pickup from Wilkinsons. Printing the new pickguard took a long time, but once done, took around 15 mins in total.
The old pickguard is still usable, as are the pickups.
I actually prefer the Wilkinsons to the splits pickups, however they were in the wrong place