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The plan is actually good and you should have done it from the start.

Consider link worth from spammy site as 0.2 as compare to a link from great resource as 8.

so if you loose 40 links from spammy site, and gained one link from good site it will be balanced or more beneficial.

Don't worry about loosing your reciprocal links if you intend to work on the plan of gaining more links from reputable sites!

In my opinion you should add "keyword analysis" into your plan as you will need to have your targeted keywords handy for anchor text when requesting / creating a backlink from any other website.

Also looking for keywords that are not well targeted by your competitors would be an easy job for you to gain.