I'm with Tom1959, do what you have to do. I used to plop an old D2 on a tv tray sit inside a shower to print. Your cart looks pretty sturdy (Much more so than a tv tray!) and if you keep the head low when transporting the odds of tipping go down. Larger wheels might be a good idea as well. Make sure you find a 135mm lens (the Nikons are usually a steal) to keep the head height as low as possible when printing.