What about '70s to mid-'90s van style? Vans used a vertical steering box in front of the axle with two universals to connect the box to the steering shaft. Rack mounted to frame in front of the axle could connect to steering shaft in a similar fashion. Even if the rack turns out to be unworkable, a front mounted box would allow the steering shaft to pass over the starter (make sure to plan a path for starter replacement!). Some guys heat and bend the spindles to move the tie rod attachment points when swapping spindles side to side (you want correct Ackerman angles). Aftermarket is selling spindles for a number of different applications so new may be an option.
It appears there are a number of options for relocating the starter. I'm thinking that you already know this and there's a reason why that's not a valid option. But in case you haven't seen this info, here are a couple of links:
https://www.4btswaps.com/threads/4bt...osition.33610/
https://www.turbodieselregister.com/...ocation.96633/