Phil,
To reduce your pic sizes, just use MS paint (probably under accessories folder in the programs folder), open your pic, click image, click stretch & skew then reduce horizontal & verticle from 100% to say 30% in the stretch box. After that save it & check the file size. If its < 50kb you'll be able to upload it to CC. If not reduce it more.
Plenty of blokes (including myself) would really like to see that great idea with the battery of yours
I also think the problem with paint & exhaust shops is that they know yoou don't need your car back ASAP. So other work comes first - which is a pain in da A$$.
Cheers