Sounds great, Phil. But with that size wire, you may want to double check that you are not charging your batteries at too high of a current. From what I have read, it seems you should not be charging a battery in excess of a C/10 rate. The C/10 rate is a charging current in amps equal to 1/10th of the battery's capacity in Ah. So with 2 large Trojan T-105s, weighing together about 130 lbs and a combined capacity of 225 Ah, they should never be charged any faster than ~23 amps. The battery that came with your TM probably has a capacity of ~80 Ah, so it's max charging rate would be 8 amps. Charging too fast for any significant length of time can generate excessive heat, cause the electrolyte to boil and the case to crack (which will cause the electrolyte to spill everywhere), and cause hydrogen off-gassing, which is obviously a major safety hazard.
Also note that your current setup is not ignition protected. That means that anytime your TM and TV are connected, your TM will draw current from your TV, even with the engine off. That could very quickly kill your TV battery and leave you stranded.
And as Wayne suggested, you should have TWO fuses in that wire -- one close to each of the TM and TV batteries.
I had the same exact concerns and thoughts as you, and here's my solution:
http://www.trailmanorowners.com/foru...ad.php?t=10587
Dave