Hey Dan. I did a lot of research for drive on my 1/16th CHTZ T-800 dozer and went electric for all the reasons you are considering.
http://www.rctruckandconstruction.co...ad.php?t=11337
I chose 25amp (stall) car seat motors @ 12V. Of course yours is heavier than my 60lb weight model.
Have you considered 24V wheechair worm-drive gear-head 90 deg motors? They are very powerful and generally run around 100-200RPM which could be controlled with an ESC motor controller, maybe a Dimension Engineering 60Amp.
Like these on aliexpress:
https://www.aliexpress.com/item/2013...479201429.html
Or this type here:
https://www.aliexpress.com/item/250w...1-17b1309b4cc1
They have all the engineering data you'd need to assess them. You could gear them down easily with say 06B ISO or 08B simplex chain drive at say 4:1 or 5:1 which would provide an output speed at the sprockets of approx 30-40rpm and would be very powerful.