FMV vs recoup questions (with hypothetical)

First, forgive me if this has been covered before. I spent a good hour looking through search results and didn't find anything definitive, so here I am asking...

Second, I want to make it clear that I'm trying to be transparent and meet the spirit and letter of the rules, but I'm also trying to maximize my budget, so here I am asking...

The questions:

1) When documenting FMV using eBay or car-part.com or whatever, should the cost of shipping for the FMV example be included in the FMV calculation?  I.e., an eBay listing for an differential has a sold price of $200, but also shows a shipping cost of $100, is the FMV $200 or $300?

2) FMV vs recoup vs SOL, a hypothetical:  Say I bought a carb and intake as a complete setup for $250, but then decide that carb isn't tunable or functional or whatever for the challenge project, so I decide to buy a new carb for $350 to use instead.  Then let's say I find the first carb has a $300 FMV because it's date coded for a '69 CJ Mustang or whatever.  Can/do I:

A) "trade" the first carb for the new one using FMV as a trade value?
B) recoup the value of the first carb from the original purchase of the carb/intake setup, using FMV as the recoup value (up to the initial purchase price of the carb/intake setup)?
C) just deal with both carbs being on the budget?

Obviously option A is the most ideal, option B a bit less so, and option C being worst case scenario. The question is: is it reasonable to trade/recoup the value of something purchased as part of group of parts (i.e. carb/intake setup) in exchange for another of that part purchased separately?  I think the spirit of the challenge is that the value/cost of the parts on the car is what matters, but the letter of the rules is less clear.

Thanks in advance for your input and replies.  Looking forward to getting this thing done in time for the challenge!

These quotes from the $2000 Challenge Rules may help: 

...

You may not list fair market value instead of purchase price on your budget unless you do not have a receipt from the purchase, or depreciation/appreciation has drastically affected the car or part’s value.

...

Shipping counts toward parts prices.

Thanks for the reply.  A lot of room for interpretation there, so I'll try to do what I think complies best with the rules.

for #2 - if it's not on the car, it's not in the budget, right? So I would say B in that case. 

I wonder if the carb/intake would be treated as one of those "lot" buys where you assign a fmv to each part, figure out the percentage of the total price each one is, then deduct that percentage from the purchase price for either your recoup or just cost?  (Ie using the numbers below, I'm not sure if it would show up as $250 minus $166.66 for recoup or if it would just show up as $83.33 for the intake with no recoup)

eg:

carb/intake bought for $250 

only want intake

carb fmv $300, intake $150, total $450

Carb 66% intake 33% of $450

carb 66% intake 33% of $250

carb $166.66 intake $83.33 of $250

I do think that is a completely reasonable approach.  It's clear that if I sold the carb for $300, or $100, or $500, or however much (regardless of FMV), that would be recoup applied towards the carb/intake cost, but that goes against the recoup limit. New carb would just be added to budget at cost. This percentage-value-of-parts-lot approach would not effect recoup, which might have advantages later.  Either way it's good to have options.