I've been looking at the workchamp and outrider I've got sitting around and doing some measuring. It appears to be possible to add more backtools (Outrider +1, WorkChamp +2) by replacing the the backspring for the knife and metal file with the one used for the corkscrew layer. I'm not sure what backlayer tools exist in the ecosystem that would work, by the space is 2.3mm wide so there should be some options.
So far I have found that the flathead combo tool from the 58mm would work as does a shortened long nail file. The parcel hook with nail file also seems like it would.
I looked through the forum but didn't see any previous posts about this, but figured someone may have been down this road before.
I'd appreciate any suggestions/advice