How to construct a DIY post-bacc

[Hypertrophy22]

I'm interested in going the DIY post-bacc route. I have read the Goro's advice for pre-meds thread (here) which recommends not to retake a C, however, I haven't taken classes in about 5 years. I regret not jumping into a post-bacc or SMP program right away, but I got a good amount of clinical experience and here I am.

I got a C in Organic Chem 1 and D in Organic Chem 2. Would it make sense for me to retake both of them over a year?

Another little dilemma- my university originally had a quarter system and a normal academic year had 3 quarters (minus summer quarter).
On this system I got:
C in Gen Chem 1
D in Gen Chem 2
A in Gen Chem 3

This would be traditional Chem I and II split into 3 courses. The grades I got confuse me also, but my question is does this put me in a place where it would make sense to retake an entire year of Gen Chem or no?

I also never took biochem in undergrad so I would add that to the list.
I'm thinking no more than 3 courses a semester considering I will also have to work full-time.
Would it look bad to only take 2 courses at a time if it came down to it?

I'm thinking for the first semester back:
Organic I
Biochem
+1 other course.

I'd appreciate any input on what would make the most sense for me to do in this situation in terms of which classes outside of the reqs to take and which of the reqs mentioned I should definitely retake.

TLDR; short version:
I got a C and D in Organic I and II respectively, should I retake both?
I got a C, D and A in Gen. Chem I, II, III. Should I retake them?
What other non req courses should I include in a post-bacc?

More importantly, how valuable is doing well in a DIY post-bacc versus doing well in an SMP program considering I've been out of school for 5 years?

Thanks!