Welcome from another newbie! It's a disease with no cure, and nobody's really looking for one
As far as the 45 mph tops, I don't think ANY of us buy these to have a dragster. If I wanna go faster, I'll go get in something else....or plan my trip a little better! It's more about looking good doing it, and what better way to do that than to go slow enough for everbody to get a really good look?
Ol' Blue is going to be a worker. Not a hard and heavy worker, sure, but not a "oh crap there's a speck of dust on the top of the differential" beauty queen either. I've always wanted something that will tilt up and empty itself without the aid of a shovel, and now I have it.
Really nothing to getting them to run. They'll go just fine, it's getting them to stop that's the trick. Even with the original brakes, they WILL stop....eventually. I learned to drive in a single-pot F6 that had been stretched with a drag axle and had a 24 foot grain bed on it. Dad stressed two very sobering things: Approach every car/stop sign/intersection with the expectation that you will not stop with the brake pedal and to be pleasantly surprised if it does happen, and two, with 40000 pounds of grain in a wood box behind you, even if you do stop the truck, the box might not stop as quickly.
Not trying to scare you, it's just a very VERY different way of driving than with the 4-wheel disc antilock brakes of today, where you can go screaming up to a stop sign and stand on the brake pedal and go from 70 to 0 in three feet. To this day, I find myself using the brake pedal so rarely that I've been pulled over for a faulty brake light switch. (Anybody else who grew up driving these things have this happen?)
Sounds like you can keep yourself in budget, or reasonably so, with your prospective purchase, considering the way you describe your 'adoptee' and the climate I imagine you live in.
And this is how we learn, is to jump into things we don't already know.
