Use #500. Bringing home a 6-7 ton of firewood. First real use I've done since pulling the deuce home. I didn't lay in enough firewood back in the summer. So it was time to get some. The wood years I use is about 60 miles each way and cheap. Stuck with green wood unfortunately, but better that nothing.
I'm rambling. This load barely squatted the tires. Pulled great. Did about 60-65 mph both ways running 1800-1900 rpm. Doesn't get up to speed as quickly as with the T-138 case I feel, but on the highway the greater top speed makes up for it. On flat land and moderate hills it hold the speed. You'll know whenever there's even a slight incline in the road though.
All in all I'm happy with the swap, and I think I'm getting better mileage with the lower rpm's. I wouldn't have done it if the original case hadn't died. NOT A STRAIGHT FORWARD CONVERSION. Haven't got a new front shaft made yet either.
The block heater is amazing. Been around 10 degrees most mornings here's. Plug in the truck for a hour or two, and he fires right up. Need one in the cranky dang deuce now.
It's amazing what some people consider slab wood. Julia is getting a new bench come spring