93 240 Wagon Rear Door Speaker Recommendation

[Martynj]

I have a set of 4 inch Polk's to go in the rear door (b/c that's what crutchfield recommended ). But after taking the door panel off and the stock speaker out I'm realizing that the stock size is definitely larger (maybe 5.25?).

I'm reluctant to stick w/ the 4 inchers knowing that a larger speaker will fit and larger = better sound.

So my question(s): Is the correct size 5.25 (none of the stock measurements are the same as a standard 5.25 speaker, yay volvo)?

If so does anyone have any recommendations for a set of speakers under $100 that definitely fit clearance wise?

Thanks,

Marty