I assumed it would be in the same spot but wanted to verify. I'm thinking it might be cool to replace the J pup with a T40 toaster or even a MM bucker at the bridge position but I want it to do a solid P tone as well.
As long as you can get that P pickup soloed, it will do a solid P tone. My Forum Plus is loaded with Wildes (P46 and J45L). It's a perfect match. I did do the ungrounded blend control (big thread about that here on TB). Despite the P46 being wound for more clarity, and my use of a 500K tone pot for more air, a little roll back on the tone control gets it right in that classic, solid P tone.
When I was converting a Foundation into a T-42.5, the best sounding pickup combo was a SF in the neck, a Toaster in the bridge. As per my goal, it eventually had two Toasters. To me, the SF sounded better in the neck position vs the Toaster but what was missed in tonality was made up for aesthetically, it certainly looked cooler with both Toasters!
That said, If I was doing a P/J mod, the P/Toaster pickup compliment would be my choice. It's a more
unique combo, and certainly
more Peavey, which is what we like around here. haha
I would also try to have the switchable option of putting the P in parallel and for sure the ability of splitting the Toaster to the neck side coil (placing the Toaster with the bridge side coil in the former J rout). That way you can get some settings with more clarity and the soloed single coil of the Toaster would have a little more oomph at that location.
Peavey's choice of putting the bridge single coils centered at 32" from the nut is rather thin, harmonically. It's great for slap, though. I almost never solo my Foundation or Forum Plus bridge pickups, just too bright.
A 60s J bass has that pickup at 31.4" and a 70s J has it at 31.75". With the above mentioned Toaster location, the neck side coil is at 31". It sounds pretty darn good soloed and single coil there!
FWIW, I find the MM pickup in the bridge is also a nice combo with the P pickup. They tend to match up well, sometimes even better if the MM pickup is traditionally wound (two 4K coils) but wired in
series. Same goes for a dual J pickup, it just works better with a split coil P pickup, both in tone and volume. My '00 US DLX P 5er has that combo.