It’s been a long time since I accidentally insulted somebody. To be clear, if I insulted anything it’s the concept and not you personally but either way you’re insulted and for that I apologize.
The guys on here will bend over backward to help but getting short with any of us doesn’t do the forum any good and has run off some top notch guys. I’ve lost count of the times that a difference of opinion was met with disrespect.
Back to the topic....
The wrecker option is the second best to hauling it. Having towed cranes and other machines with similar front ends to yours I think flat tow would be like pulling a hay wagon 750 miles not to mention it’s two more old tires to keep tabs on. At one time I believe you could rent those 5th wheel wrecker attachments but I don’t recall where I saw that. Maybe a little searching will find one. Worst case buy one, make your trip, then sell.
Another thought is if towed you’ll have to pull the drive lines and/or axles plus make sure the hubs stay lubed. If there’s any documentation at all regarding the purchase of the crane I’d take it along so that you can prove it belongs to you otherwise they may try to say you’re acting as a wrecker service. I’d say anything at all helps because we all know the man assumes you’re up to no good even if you aren’t. Anything we can collectively think of to prevent a delay or fine is time and effort well spent.