I don't have a Krebs for Mt. Diablo, but for Metcalf it shows 3 sets of 3 chevrons, one 1 chevron and then one 2 chevron right in a row.

Gilroy Hot Springs shows 3 sets of 2 chevrons on Roop Rd. and then one chevron a little later. Looks like you'll have a steep descent down Canada Rd. on the other side of the loop, so be careful.

Don't know how this all compares to Diablo... but Diablo is long (like 12 miles, I think?) These climbs only look to be about 3 or 4 miles on Metcalf and maybe 2 or 3 miles up to Gilroy Hot Springs.

Good for you making it up Diablo! WOO HOO! I think I still don't want to know.