doing a hack for a xbox 1 drive like for example the samsung drive would be a great foundation of knowledge to hack the 360 samsung drive.
for one the use the same core processor the 8032(8051,8052 compatible) so you would be learning the same instruction set.
the xbox 1 samsung firmware is 128kb but the 8032 is limited to 64kb program space. they get around this limitation by using bank switching. so when disasming the firmware split into 2x64kb banks. there is always common code at the begining of each bank as well so the begining of each bank will be identical.
the xbox 360 samsung firmware is 256kb or 4x64kb banks.
so many of the skills needed to develop a firmware hack for the xbox 1 samsung would apply directly to the 360 samsung drive.
you could also use the same tools. disassmblers, assemblers, and/or simulators.
here are few tools suggestions i have been using in my work that were recomended by Tiros over at xboxhacker forums.
1)Dis8051
http://bit.kuas.edu.tw/~8051/2)Asem51 by W.W. Hienz
http://plit.de/asem-51/i then also like to to use Emulator 8051 V1.0 by TS Controls it is also at
http://bit.kuas.edu.tw/~8051/then there is MIDE-51 at
http://www.opcube.com/home.htmlwhich is an integrate developer enviroment that supports ASEM-51 and Emulator 8051. so you can compiled and simulate your firmware very quickly.
i don't know where i was going with this but all the tools will help you with a xbox 1 firmware as well a 360 firmware hack.
Sorry if i am incoherent i am so high right now its amazing i can type.
Peace
BlueCop
addition: i forgot to mention i don't think a xbox 1 firmware hack would be useless. there are other uses for it besides playing copies on live if you think about it.
I forgot to mention as well that i have posted a method of read/writing the firmware of a TS-H943A with just a computer with a sata controller, a sata harddrive(your 360 drive works) and the dvd drive itself. it requires booting into dos and hot swaping some sata cables then using a mtkflash 1.83c. It is a varition of a something similar by germania and it tacked onto his thread. if you want info on it go over to xboxhacker
with it you can backup and overwrite your firmware on your Toshiba Samsung drive no problem. it doesn't require you desolder the flash ethier. which is really difficult because it is encased in epoxy.