FAKO vs FICO and Newbie tactics

Hey everyone! Great forum--I'm very glad that I've found this and thanks in advance for all of your help.

My wife and I are looking to refi our house this next year. I thought that before we got started I would try to clean up our credit. I had a question about the FAKO/FICO scores I got from the reports and just wanted to post what my strategy is thus far.

The scores I got from creditreport.com showed scores of:

EFX 666
EXP 692
TU 715

After finding that I had 13 derogatories I knew that I was in for a haul to repair the items and would need a monitoring service. I chose PG. Their scores came back drastically different:

EFX 567
EXP 583
TU 593

Why such a huge descrepancy in the reports? In your experience which is probably closest to what would appear on a credit report pulled by a mortgage lender? I'm assuming the lower of the two and working up from there.

Ok, On to strategy. As I said before, I have several negative remarks that I am trying to get fixed. Here's the breakdown:

5 tradelines of student loans each showing 1 60 day late from late last year. I talked the OC into faxing a letter stating the loan was in deferment during the period shown as delinquent. CRRR'd this and request to fix to the CRA's. Hopefully these will drop off.

1 revolving store credit showing 2 30 day lates in the last 4 months. Same thing---received fax saying I was "current and in good standing" from the original creditor. CRRR'd CRAs and hope for speedy removal.

1 Sears MC with several 30 day lates the last year. I was listed as AU. Called and was removed as AU with OC the disputed as "Not Mine"

1 Sears opened in 94 and paid in full almost 3 years ago with no further activity. Did the 1-2 punch requesting validation from OC (yeah, they are going to run out to verify a 3 year old paid off, closed account) and disputed as "Not Mine" with the CRAs.

1 Chase closed 2.5 years ago with 0 balance. I was an AU but decided to let sleeping dogs lie and disputed with CRAs as "Not Mine".

1 Chase closed 2.5 years ago with 0 balance. I was the owner of the account so I did the 1-2 punch.

1 Discover card paid off 2 years ago and closed with 0 balance. 1-2 punch.

1 bank note for a car loan, paid in full with a 60 and 3 30 day lates. last account activity 3 years ago. 1-2 punch.

Does this battle plan seem ok to you battle hardened vets?

Thanks!