My 77 is the same as far as water pump studs. When I replaced my pump last time my engine was out it didn’t come with the studs so I had to move them from the old pump to the new.
As for the clutch, Hayes seem to make good units. Is the 10th an AC car? If so may want to consider a HD clutch vs the SD but I ran an SD on my 77 for a while with a 5 blade fan before I reinstalled my AC and it did the job just fine. Now with AC I tend to start to warm up at idle, possibly because I’m running a 403 shroud on my 400 and wonder if the fan depth isn’t right but either way, a 7 blade fan and HD clutch slowed the warming up at idle with AC on. Didn’t stop it though. No AC, I rarely see 185° under any conditions.