40 Gallon isnt the best option, you should try to find something a bit larger.

Also as far as lighting arrangements, you will have to mess around with this and experiment a bit. You may need to try different bulbs in different positions to get a good temperature gradient as well as a hot enough basking area.

In my enclosures I use a 160w MVB for the basking area (8"x8" slate) plus another 50w basking bulb to get the basking area to reach up to 136F. Luckily I am able to keep stable temps in my house with just those bulbs. I have a warm end ambient of 94-98F and a cool end ambient of 83-86F. This is in a 75 gallon tank measuring 48"x18"x18" which is the minimum I would recommend for a Uro (aside from egyptians of course)