Wiring a Series 2a '109' tips?

[SG1 Bones]

I am planning on rewiring my 109a but just found out recently that it is originally a positive earth unlike the alternator. Versions that are negative earthed. I plan to put in an alternator and maybe work off the S3w/fog lights electrical diagram as a base to start. Anyone with suggestions, tips or ideas?
Thanks :confused:

[p38arover]

Google converting positive earth to negative earth. It's easy. Lots of threads on the 'net.