Certainly would suggest telling him you adore the gift but simply do not have the room for it and that a return or exchange for an equally thoughtful gift he can pick out for you is needed. It’s truly not a problem, in my eyes. Tell him you love it, you love him, but you can’t accommodate because of ______ situation.

If your partner would get upset at you telling them this, there may be a maturity offset. Ability to accept that things will never go perfectly your way is crucial to relationship survival as is the understanding that your partner has their own unique abs individual thoughts outside of your own wants and needs. Let’s hope he doesn’t react that way and if he does - that’s a mountain to climb another day!