Gary, Many thanks for your reply. I have discovered that Sunbeam Car Parts (formerly Sunbeam Alpine & Tiger Spares) in the UK sell a 4 way fuse box with spade connectors for around ₤20 as an upgrade to the original. The link is https://sunbeamcarparts.co.uk/upgrades/fuse-box-4-way
I guess if one is not enough two could be installed. Under the dash is a good idea except that access for fuse replacement would not be as easy as under the hood. There is also the option of inline fuses and people talk about using relays though I am not sure where and how.
I am still wondering what additional circuits to fuse. For example I burnt the wiring when the dip switch on the floor broke off and shorted out, so that’s one obvious target. It’s too bad there isn’t a diagram around with recommendations on upgrading the fusing and wiring.
I have been wrestling with the alternator option, but it requires changing everything to negative earth. Moreover, most of the posts I have read discuss a modified bracket required though I have the impression that this is mainly with respect to Tigers. It appears that, apart from being more modern technology, the advantage of an alternator is that it puts out more current at lower revs and therefore does not discharge the battery and can supply a bunch of accessories that require power. That said I don’t have lots of accessories and the car ran well for over 50 years with the generator (dynamo) for which it was designed, so I don’t think the extra expense for an alternator, possible installation issues and the hassle of changing to negative earth is worth it. One site I came across sells a Positive Earth Dynamator Alternator Dynamo to fit a Sunbeam Alpine or Rapier. I looks just like a dynamo and would presumably fit and would have the advantages of an alternator without going to a positive earth. Sounds almost too good to be true. I have emailed them for more info. The link is https://www.qpbaid.com/index.php?main_page=product_info&products_id=614309.
It’s interesting that even with extensive internet searching, Tom Wiencek’s articles keep turning up http://www.team.net/www/rootes/sunbeam/alpine/mk1-5/techtips/altconv.html and http://www.team.net/www/rootes/sunbeam/alpine/mk1-5/techtips/cvtgrnd.html. If you have the link to Joe Parlanti’s article I would appreciate it as I couldn’t find it.
It seems that there are many owners with good mechanical skills but fewer electrical experts!