Radio fuse size/amp rating original

[mk]

I've got a bump radio here with the original lead (with inline fuse cartridge) from the under dash connector... but no fuse.
Does anyone remember the size/rating of this fuse 'cause I sure as heck don't and can't seem to find any info anywhere.
Thanks!

[Fraser]

'67 owners manual states SFE-14 in the fuse panel, which seems high to me, my '67 Lincoln only uses a 7.5 amp. I have seen those radios with an inline holder, I would just try a 7.5 and see.
Edit, I just looked in my '67 Ford and Mercury truck service specifications book, it shows radio, SFE 7.5, cartridge in feed wire.

[mk]

Thanks! I realize that back then the radio was an optional accessory, but I would have thought they were common enough that the owners manual would have info but no dice.
Even at that, it seems to me the original fuse in the cartridge was very short, like 5/8" but the sfe 7.5 shows as 7/8" long. Guess I'll have to dig through my electrical goodie box to see what I can scare up