Convertible windscreen dimensions- Help

[stimsonron@yahoo.ca]

Help? I have 1995 BMW 325i seats mounted in a 47 Ford convertible streetrod. I would like to install a wind deflector screen (the type that fills the rear seat area and extends up above the headrests. everyone that I have talked to about these wind deflectors say that 70% plus of the wind coming from the rear is eliminated. I would like to install one of these but my dimensions will be slightly different that a stock BMW but I'm pretty sure that one of the stock units will fit in my application. I do not know anyone that has one and the manufacturers will not give me dimensions so I confirm the fit before I purchase one. To save time heres the dimensions of the base that the windscreen must be equal to or slightly smaller than. Widest point of base at front= 44 1/2". Narrowest point at rear of base =36". Depth front to rear of base 13 1/2". The upper piece is not as critical but 14 1/4" would be optimum. I realize that my car is not a pure BMW as most of yours are but I'm appealing to you as car guys to help me out is possible.
Thanks in advance