Mike, it sounds as if you're a great constructor - such a fantastic array of tools.
I shouldn't laugh, its what one can achieve with them that counts. I'd be very interested to see your mod to your finderscope e.p. to insert the LED. having a SCT, fine focussing is mirror movement although I'm sure a better arrangement could be dreamt up for it at the e.p. end. Probably worth a bit of thought.
What have you got for 12V. I amusing an el cheapo jump start from "Super Cheap". Cost me under $65. Had no problems. Never run it down below about 40-50% and recharge immediately after. Now if I had an astro shed.........
I can only wish. My suburban block is just not suitable.