1988 240 DL 103,000 miles.

My bentley and haynes manuals do not cover how to replace this. Can anyone give me a quick run though on what steps i need to take to replace this junction. THANKS!

Pretty straighforward. More or less like this:

PB blaster all the flare nuts one day in advance

Hold brake pedal down 6-10" with block of wood.
Using a high-quality flare nut wrench 11mm, crack one nut and let the excess fluid drain. Go around and crack open all the nuts BEFORE you fully remove any. Once you've determined all will open, remove them all.
One bolt holds block to frame.
Wipe/spray down all the lines with brakekleener and clean rag.
Install new BJB, but don't fully tighten bolt. Leave it a little loose.

Can't remember which one, but the first two lines you put back on are the hardest ones when you wiggled them off. Remove each little yellow plug as you go along.
Just loosely finger on threads of each fitting till all are on. You'll need a little wiggle room from time to time.
Once they're all on, tighten them up. Tighten BJB mount bolt.
Bleed brakes.

Most important, just take your time, don't force anything. I'ts all quite easy.

Have fun.
--
89 245 'loaded' with a Great Pyrenees

"Hold brake pedal down 6-10" with block of wood."

1" to 1.5" is far enough to keep Master Cylinder fluid from draining while lines are open on pre-ABS 240s.