As a seller who is in no hurry, you can just list the car with a very aggressive asking price.
If someone bites, then it's time to shop for a 3.2. If not, you've lost nothing.
If you sell high, and buy low, you might even arbitrage the situation and make a few bucks.
Here is an 86 Targa with similar miles that just sold for $22k
http://www.ebay.com/itm/1986-PORSCHE-911-TARGA-/331143498260?_trksid=p2047675.l2557&ssPageName=STR K%3AMEBIDX%3AIT&nma=true&si=IjkCSBhyiaqK0jLLqFBzmj vdXsE%253D&orig_cvip=true&rt=nc