Progress Thread Block transplant (and more)

Lol... Hate that. Dropping the bolt or nut and then repeating "please fall through... please fall through..." I love tubular k-member and A-arms in 2 of my cars. The stock stuff catches them way too often. Anyways, your bolt is probably along the rail/edge of the k-member below where you dropped it. Run a magnet along it from below.
 
The coolant drain plugs in my stock block were useless. They were 1/4” Allen key and the Allen key rotated and stripped without budging the plug. I’m thinking about using some kind of petcock drain for coolant plugs on the new block. Do any of you use anything like that or do you have a recommendation?
 
Do they make the same size and thread plug but hex head? Not a coolant plug on an engine block but it’s a common ‘upgrade’ in the Toyota world to replace the front differential plugs that come Allen/torx (?) with a Lexus hex headed plug for this exact reason.
 
I’m down to one bell housing bolt before I can lift the short block out. I need to put tools away, make room on the work floor to move the hoist around and get the engine stand out of the shed. It’s leaf season too so that’s taking up my limited time as well. Little by little it’s happening
 
Pretty sure there are screw in hex plugs where the freeze plugs go on the Boss block. I have never had a drain on the block and have just dealt with it. I don't plan on pulling a motor very often so I have not seen the use / benefit but I can see where some would like the option.