47-55.1 Four-link questions

[TX3100Guy]

Several of you are following another thread I have going at - https://67-72chevytrucks.com/vboard/...d.php?t=849339

That thread started out when I found an oil leak but couldn't quite figure out where it was coming from and why. I wondered if my elimination of the road draft tube and substitution with a PCV fed into the intake could be causing back pressure (HINT: it wasn't). As the thread progressed, the result ended up with me 1) find an cracked crank end cap, 2) pulling the engine, and 3) sending it off on a pallet to be rebuilt and overhauled.

Since I am a member in good standing of the "While I'm at it club" and find myself bored while waiting on the engine, I've undertaken a few miscellaneous projects. I traded an old four speed transmission to a buddy (plus a few bucks) to paint the bed, which is all new Mar-K metal in primer).

Now I'm reconsidering the leaf spring suspension on the rear of the truck. I've been looking around at different four link systems with coil-overs. With the engine out, truck bed removed, there will never be a better time undertake an upgrade to the suspension.

i have two questions 1) does it make any sense to have a four-link in the rear and still keep the solid axle and leaf springs up front? and 2) Does anyone have an experience with the "bolt on kits" (still need to weld the axle brackets)? I'd like to hear (and see photos) of the work involved and what your thoughts are afterwards....would you do it again?