Al, your silence is deafening, are you getting splinters?
Hi George,
At this point a multitude of opinions and experiences have been stated that are relevant to choosing the current rating of an SR fuse, including opinions from technically knowledgeable people such as you and I. Those reading the thread who intend to try SR fuses can and will form their own decisions as to how to proceed.
For those who may be pondering this question, though, I'll add the following question and answer to my previous comments on the matter:
Question: Are the protection characteristics of a stock 5 amp fuse, especially the combinations of current and time that would cause it to blow, most closely approximated by an SR Black 5 amp fuse, or by an SR Black 6.3 amp fuse, or by some other SR Black fuse?
Answer: We don't know.
Best regards,
-- Al