This has an El84 & a 8" speaker does it not?
I have an AD30VT & a Fender Champion 600 with a 6V6 & a 6" speaker.
Here's is what I've been doing & getting excellent results with it.
I play them both at the same time using a Barber Paunch Pad to split the signal & adjust the relative levels.
Of course, this might not work for you as the Peavey sounds like it is louder than the Champion.
I've had the job as Santa's tester & have had to suffer the pain as his elves take back the item & squirrel it away until the big day.
It hurts, but it is worth it. Otherwise you'll end up with one of Esteban's guitars.