SVX are awesome. I looked at one for sale a while back. My favorite Subaru alongside the 2nd generation BRAT. What color? How long have you had it?
I had a look at
https://www.google.com/search?q=Subaru+SVX+cutaway. So, two motors back-to-back in the middle facing the ends? That might could work.
I'd look at the overall ratios of various single-speed motors.
Tesla -- 9.37:1
Leaf -- 7.94:1
Toyota MGR -- 6.86:1
GNK eAxle -- 12.5:1