We do have a couple magguts compatible basepads designed to fit the XL frame/gripmodule, which work on the P365 XL and P365X.
The AXL-12 Hybrid basepad, shares same external dimensions as the regular Proledge basepad for the XL frame/gripmodule, but the internals are designed for magguts compatibility. The AXL-12 will also work with the OEM basepad with the included shim.
The AXL-Hybrid Reach Aluminum Basepad which is designed for magwell flare use, is also OEM spring, and magguts compatible.
Links below
AXL-12 Hybrid basepad for P365X/XL 12 rnd OEM/MagGuts Spring
AXL-Hybrid Reach Aluminum Basepad for Sig P365X/XL
We do not have a magguts compatible basepad for the standard P365 frame/grip module, or any to match the larger backstrap of the Wilson Combat grip modules.
Unless a basepad is specifically designed to have the extra void in the basepad for the flat spring to compress into, it will not be able to add capacity.
See the difference internally between the Pro Ledge basepad for XL 12 rnd Mag , and AXL-12 Hybrid basepad for P365X/XL 12 rnd OEM/MagGuts Spring basepads.
Unless the basepad product page specifically states magguts compatibility, it is not compatible.
The basepads above are the only magguts compatible basepads we offer at this time.