REESE PLANS MARRIAGE TEST RUN

Gun-shy gal not ready to go all the way

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LOVESTRUCK Reese Witherspoon has fallen head over heels for financier Oliver Haarmann — but after two failed marriages, the cautious cutie wants to put their romance to the test by moving in together before tying the knot, sources say.

According to tipsters, The Morning Show star, 49, is on the fast track to cohabitating with the 57-year-old New York-based businessman and likening the future arrangement to a trial marriage to assess their long-term compatibility.

In March, the lovebirds reportedly checked out a posh Big Apple apartment in a new building designed by famed architect Robert A.M. Stern.