I did work with the weight calculator that Tru-Hitch offers, I used a bunch of different numbers to try and figure out the weights that get transferred and it isn't as bad as expected. Even with that, my margin of error or safety factor (at least DOT ticket wise) is too close for comfort. Basically if I don't have the knuckle boom Perk is fine, once the knuckle boom is there, it is not. I really don't want to get rid of the knuckle boom or put a smaller one on it, I feel I am already not where I want to be lifting capacity wise.
If I want to still use OMO, I would have to add tandem rears (was going to do this anyways) and mount the knuckle boom on the back of the truck, this makes it impossible to haul a fifth wheel or goose neck trailer and I am not sure I want to be limited to tag trailers only. I could rework Perk, but in the end it becomes a big truck, I was trying to avoid making another big truck, Perk is very maneuverable right now and adding length to the chassis and another axle is going to take that away. Before you say to sell Perk, I have a very good reason to use Perk in some way, my registration is almost $400 a year cheaper than any other comparable truck due to the fact that Perk was a "glider kit" and cost a fraction of the cost of a new truck ($50k versus $125K), this is real world savings that over the long term will add up to a lot of money. This doesn't mean I can't change or reconfigure Perk, it just means that I should use the cab, VIN, and title to keep realizing these savings. Plus Perk has less than 9000 miles on it, so the cab is essentially new.
I am sort of thinking it may be time to admit defeat and just build Perk into what I need and send OMO away. Of course that gets me to the point that if I am going to essentially start from scratch and build an entirely new frame, I might as well make Perk a 6x6 so that I have full offroad abilities as well as on highway. No matter what happens I am probably looking at another $20k to do this, plus time. I see trucks that fit the bill from time to time, but they are generally $60k to $100k and I know I would still have to do some work to make it what I need. It is pretty crazy when I stop and think about all this, but I know I can't recoup much of my money invested so far without doing a lot more work.
The other option for Perk would be to remove the knuckle boom and set things up as a dedicated single axle tractor, I could also make it a 4x4 for a reasonable price since I already have the setup in the Diamond REO with the bad frame. If I did that Perk would weigh quite a bit less, opening things up to being able to haul a heavy truck with the Tru-Hitch while being legal. I do need to figure out how much weight would be added by the 4x4 versus the savings from the knuckle boom. I think the knuckle boom is about 7000 pounds, the transfer case will be a thousand pounds, front axle and driveshafts will be 2500, that would give my a couple more tons of capacity and fro the charts that would be about all I need. I just don't know if it will be worth it in the end, although I could actually shorten Perk even more if the knuckle boom was gone, that would add some extra abilities too.
As you can see, I have a complicated mess and the simple answer isn't so simple.