Jeep did something like it once before ... majority of the expensive development and certification, since a conversion kit would just be a set of parts to apply to an already certified model.

Jeep Wrangler Apache introduces new Mopar 6.4-liter HEMI V-8 conversion kit Mighty FC Concept features Mopar portal axles; harkens back to Jeep Forward Control models of 1950s and 1960s Jeep J-12 ...