Hydraulic seats, etc

I am just getting into reworking a 1949 Cadillac 60 Series Sedan.  I am also a "newbie" when it comes to creating a rod, albeit I have admired them for years.
Regarding the hydraulic seats (and hydraulic windows), what is recommended for converting them to electric,i.e. no sense re-inventing the wheel when someone certainly has already done it.  The engine and tranny are out of this car, and I will be eventually putting a chev 350 with 700R4 transmission in it. Any syggestions regarding that process, rear end changeout, etc. would be appreciated. First I have to
get it rolling.  Back to the hydraulic seat...I will first need to get it back away from the steering wheel so I can climb in (I am a big cat).  Is there a manual method to move it, or do I have to get a 6 V battery and do some re-wiring?  Lastly, are there back issues of R & C that goes thru any of this?  Thanks, JJRJR