Cat 580D CK - Loader Hydraulic Tube Replacement?

Hey everyone! I have been tasked at replacing the two metal tubes for the loader's left cylinder (and doing a slow overhaul in general). They have corroded through due to battery acid being left on them for many years.

The parts I am talking about are number 9 and number 10 from this exploded view:
http://ift.tt/1QrqcOw

I have the tubes and plenty of oil to do a flush and the normal array of tools, but after looking at these lines specifically, I'm not sure how to get them out. I know I have to remove the battery tray, but it looks as if the cab has to come off too.

Here are some good images of the tubes in question:
http://ift.tt/2hoBLg2
http://ift.tt/2gKYUp8

Now, in the second image above, the fittings sit directly on top of the frame. And directly above is the cab floor. A better photo:
http://ift.tt/2hoIcjs

One thought I had was to cut a door here (red square) to make an access port for the wrench:
http://ift.tt/2gKYnmQ

My question is, have any of you replaced these tubes? If so, what/how did you do the job. Or am I looking at a near 100% disassembly of the control valve to get to them?

Thanks all!

Cat 580D CK - Loader Hydraulic Tube Replacement?