72 engine compartment fuse block
 

I have not taken this unit off, but can anyone tell me if the fuses on this block are separate and not daisy chained, for lack of a better term? I also just realized, after 20 years of ownership ;), what these fuses do in regards to a 72. The top fuse is for a sportamatic, which I don't have, the middle is the starter enrichment and the bottom is for the defrost, which I also don't have working. So, I'm speculating that the only fuse that is needed in my case is the middle one, unless one of those wires is hot and supplying current to the entire block?

Fuses 1 and 2 are bonded together and have a single battery feed from the ignition switch. (Red wire top rhs terminal) Fuse 3 for the rear demister relay gets its battery feed direct from the battery via the connection on the alternator.

So if I were to purchase a new one, one that is not stock, I would need to connect 1 and 2 somehow? Actually since number 1 is not used I guess it really doesn't matter in regards to my car.
Thanks.

I guess if the original unit needs replacing and all you need is a fuse for the cold start circuit then a simple in line fuse holder like you get with car stereos would be fine, but not original. What's wrong with the fuse block that you need to replace it?

Actually nothing is wrong, just bored and want to get rid of the old style fuses and go with ato.

I took a closer look at that 3 fuse mount block today and in my 911 its mounted upside down with fuse 3 at the top and fuse 1 at the bottom. The link between fuse 1 and fuse 2 is therefore bottom left. I agree those fuses are a weak point, easily knocked out and prone to corrosion. I remember I was bored once, but it was well before I owned a Porsche or had children.

Maybe bored was the wrong word. Just recieved the fuse block and it looks as if it will work. Took old one off, decided to clean it up and I think I will leave well enough alone. That fuse block maybe old and funky, but it's been there since 72 and has really never failed me, just like the old CD unit that keeps on, keeping on.