Will a pistol grip fit made for Mossberg 500 series fit on a maverick 88?

I've heard they are made to the exact same specs just the mav is a little cheaper model etc. I'm not concerned with any answers about performance, i've shot probably 1000 shells through my mav and she's tickin' like new... but i sawed the stock off to reveal the bolt i could remove and bought a pistol grip made for moss 500 series... shouldn't it fit if they have the same specs as far as size? help!