How to Build a 240GB 6th generation iPod Classic?

I have been doing a lot of research and I haven't found an exact answer to my question. Right now I have a 6th generation 80GB ipod classic. I have run out of storage and I really need 240GB. I bought a rebuilt 240GB 7th generation Ipod from ebay a few days ago for ($274), I received it and I dont like the fit and finish of it. It looks like the wheel and faceplate are aftermarket replacements so it does not sit flush against the rear case and neither does the wheel to faceplate, there is an excessive gap around the circumference of the wheel and the faceplate, and the screen flickers at times, so I am going to return it. I primarily use my ipod for mountain biking and cycling so it gets exposed to sweat and rain. My 80GB has never failed under these conditions for 5+years, and I think this ebay version will fail very quickly.

My questions is.... I would like to know what are all the parts needed to make a 240GB hard drive work in my 6th generation ipod classic. I know if I install a 240GB hard drive in my 6th generation ipod it will only read 128GB. So can I replace the logic board in my ipod with a 7th generation ipod? I can find the 7th generation logic boards for ($60+) on ebay, then buy the 240gb hard drive ($86) and 6th generation (thick)160GB rear cover ($10) new 850mAh battery ($10). That would be a $166 upgrade..... Is that all I would need? Would the logic board be a direct swap, or would I need a different connector, screen, etc? I would prefer to just modify my 6th generation ipod since I know it works and it seems like it could be the cheapest way, and I don't need two ipods so I feel like it would be a waste to buy another one.

My other option is to buy a new 160GB 7th generation ipod classic ($230), and buy the 240gb hard drive ($86) and 6th generation (thick)160GB rear cover ($10). That would put me around $326....

I would prefer not to take another gamble and buy another ipod off of ebay, so I would like to keep it to these two options..... If buying a 7th generation is the only way, could I then put the 160gb hard drive in my 6th generation? Would it still only read 128gb max? Would the hard drive be the only thing I would need to swap? From what I read it appears all the thin (6th and 7th) ipod classics used the same hard drive connector. To make the 160gb hard drive work, would I again need a 7th generation logic board?

Do I need a new headphone jack? Ive heard that it may need to be replaced but I dont remember for what ipod versions. Does this apply to my thin 6th generation, or the thin 7th, or neither?

Could someone please give me a complete parts list for making a 240gb 6th generation AND a 240gb 7th generation. Thanks!