Giving your concern with the condition of the corrector, my number one tip is to not disassemble it to clean it.
There are factory rotational alignments of the optics including both the secondary and the corrector plate that are easily lost without proper research and preparation to maintain the original factory alignments. Newer celestrons also have the corrector placed precisely within the cell, not merely centered, another adjustment that you must be prepared to duplicate on reassembly.
So just clean the outside if you wish.
No problem with cleaning the outside surface as long as you follow accepted practices on using a fresh new loop type microfiber, which absorbs quite well, or PEC pads, available on amazon, along with an acceptable cleaner such as Zeiss fluid, also available in Amazon.
Do not use acetone, while it's okay for glass outside of a cell, it will wick into every tiny surface and cause issues.
You don't really need a power tank unless you get a dew heater. The Talentcell lithium battery packs frequently recommended here on CN are all you need for the GPS scope for several hours. I run my GPS 11 without any issues whatsoever, and the talent cell also has USB outlets to power my tablet if necessary. They are the size of a paperback book and very light, and fairly inexpensive.
You may encounter issues getting the correct time and date from the satellite, due to a quirk in the GPS standards be dating back nearly 20 years.
You may also have trouble getting accurate location data downloaded because the internal lithium rechargeable battery that maintains satellite information goes flat after a while, and it may take an hour, and even up to a a couple of days of being powered on and positioned next to a window with view of the satellites to download all the information needed from the GPS satellites and give an accurate location.
The internal batteries have been known to go bad, however, very often they just need to be charged by having the scope powered on and left on for a while.
My own GPS 11s had to be left on for nearly two days to both recharge the battery and to give proper location data.
As if that was not enough to delay getting started, you have to go through the menus and find out the version number of your hand controller, and compare it to the information on
Mike Swanson's wonderful website that provides lots of free information to help you out.
Go there, read all the tips on using the GPS scopes, and consider buying his book, worth every penny. It goes into much more detail and gives many more tips than the site.
You probably have the earlier of the two hand controllers, for which the version 4.22 firmware programming provides necessary fix to have the GPS 9.25 return the proper date and time information. Without it you get dates far in the past.
There are workarounds so you can use the scope immediately, I think the easiest is to download Sky Safari for either Android or iOS, on a phone that has GPS capability.
it's a wonderful program that can eventually control your telescope if you get the proper adapter, I use StarBT from astro-gadget.NET for my Android tablet.
But one of the handy parts is that it Sky Safari will display the satellite exact location common date and time on the screen then you can then manually enter into the telescope until you get the hand controller updated, if it needs it.
I really like the GPS 11, enjoy your scope.
Hold off on adjusting combination until you are familiar with using the scope. when you are ready to collimate it, I highly recommend starting with daytime collimation using
(You may not get perfectly concentric circles, due to slight variations in manufacturing tolerances in centering of the optical elements).
After that there are many posts on confirmation, but I am personally experimenting with the use of a Duncan mask, which you can search for here on CN. I finally got around to cutting one out for myself yesterday and I'm waiting for clear skies to try it.