I looked in my fastener guide for you. Here's what it says about the BB engine fasteners.
thermostate housing...No washers 3/8" -16 1.00" long bolt I don't know how to decribe the marking on the head...it kind of looks like a dog bone.
water pump to housing bolts...No washers 3/8" -16 .88" long bolt with an M or an A in the center.
intake...3/8 -16 1.50" long bolt with TR on the head...washers were only used on the aluminum 440+6 intake...a toothed washer was used for the negative battery cable attaching bolt...no washers were used on bolts that secured a bracket.
oil pump(oil pump to engine fastener)...two different lenths were used 3/8" -16 4.25" and 2.52" long bolts...they have an L5 marking on the head. It looks like split lock washers were used on those bolts.
oil pump(cover to pump bolts) 5/16" -18x.75" long with the dog bone marking on the head. Split lock washers were also used.