I have a 6.1 six speed in a 71 Cuda convertible, looking to mount the battery in the trunk and any ideals.
I have the hot wire engine and computer system.
Ideals on running wires inside the car?
I've heard of some guys using ford solenoid's so the main cable would only be hot for safety, is this even needed??
Also, what about power distribution blocks??

Thanks...

Ideally, you want to mount it in the trunk, hide the wiring away..............

Lots of ideas and lots of approaches. If you are drag racing need to check sanctioning bodies for shutoff requirements. I am not so here's what I did ('70 E). Battery mounted on right side of trunk just aft of the fuel fill tube. #1 gauge positive run over to the drivers side and down through a grommet in the trunk floor to the drivers frame rail. The positive cable runs like the fuel line on the pass side - except it is on the drivers side - under the car up to the starter. 6 gauge from the starter to the fender relay and 6 gauge from the fender relay to alternator with 10 gauge fusible link.

Grounding is handled by a 2 gauge wire from battery negative to the trunk floor and bolted through the lip of a rear frame rail plus a 2 gauge from the rear frame ground to engine block that follows the + cable routing. The 2 gauge ground to engine block was added to help hot starting... which it did.

Works fine. No added relays and no high amp wires through the pass compartment.

I agree. Moving the battery to the trunk is ideal.

Yes many ways to go. as said go thru the trunk floor to the subframe for the neg cable in the trunk. You want a "continuous duty" type furd solenoid if you dont want the front to rear large positive cable hot all the time cuz if you run it hot all the time you dont need the solenoid but instead run from the batt positive post up to the starter. I ran it hot all the time & We used 1/0 or 2/0 (I forget which) welding cable on the stock car which is overkill & ran it straight from the batt to the starter. By the nature of it welding cable is multi stranded for flexing resistance and very thick insulation (it ain't gonna get grounded out anywhere) and run the alt to the starter relay and the starter relay down to the starter and an ammeter in series in that (starter to starter relay) line. then T from the starter relay to the bulkhed/fusible link. This will show if the batt/alt is charging or discharging. & if no ammeter is used a person could run the alt to the starter and the starter as mentioned directly to the trunk battery same as with an ammeter so all (3) are directly connected in line with large cable then run a line from the starter up to the starter relay and from there a fusible link to the bulkhead/underdash like normal. EDIT the parts house furd solenoids are meant for passing large current for just long enough to start the car (several seconds or so). With it "on" all the time for hours and hours that you are running the car you would need a special "continuous duty" type of that solenoid (they are available) then there is the trunk shutoff the NHRA (& others) require & I ain't up on that deal (which cable it goes to if that matters but I think it does)

My most recent battery relocation went under right rear seat area, which I felt was a better end solution, but required more effort/compromises, like ditching the rear seat.