Q. What screws should we use to attach the pew brackets to our pews?

 
A. The bracket mfg. offers 2 lengths of screws, (3/4” and 1”) either or neither of which may work for you.
 
I just got through replacing a lot of brackets at my church and I found that on pews where the previous brackets had been installed perfectly, and the hole had not been made larger by a loose bracket, the 1” length was usually OK. (You could use the ¾” on a brand new install but otherwise they are too short.)
 
The more typical experience was where the hole on some pews was too large to use the mfg screws and I had to make a couple of trips to the hardware store to get larger screws.
 
I used several different sizes depending on the situation. It was clear that one person before me had used a certain style and type of screw when repairing the kneeler brackets, and another repair job the previous guy used a different size. (Both were not what I would have used so it added to the difficulty in fixing the kneelers)
 
Also, we had the floors re-done recently and when the floor guys put the pews back down, they used 3 different styles of fasteners (who knows why) and each one required a different replacement screw size depending on how well they had driven the fastener.
 
The factory kneeler bracket screws are black, like a drywall screw but a little harder and less prone to snapping. That said, I used a zinc #10 head because our hardware store didn’t carry the hardened ones and drywall screws will snap in the hard oak of a church pew.
 
The most common size screw I used to make the kneeler repairs was 1-1/4" length #10
 
In short, you will just need to see what works best for you. I would get a box of 1-1/4, 1” and maybe even some 1-1/2” ones although you want make sure they don’t bust out the other side. You could probably used the #8 screws in some spots, but if your experience is like mine, the #10 fills the gap of the previous hole a bit better.
 
Finally, I would recommend you to have 3 to 4 plastic boxes to keep the different screws in so you can slide them along the floor as you work. (the box they come in slows you down) and also to hold your old screws as they may be reusable somewhere else. You may find you have to change out the driver bit, as I did each time I came to a different fastener. I had one cordless drill, but two would have been better. If you are also replacing the kneeler stops or rubber bumpers, you will want a pair of channel lock pliers to remove the old rubber stop and a rubber mallet to install the new ones.
 
Hope this helps.
Thanks and Good luck,