hi marshall,

i've done a little research on my own with this by removing the speakers, measuring and speaking to crutchfield consultants. from what i've gathered is that the speakers are oddball sizes (indicative of the time they were made).

basically from my understanding, this is what i've found:

the front speakers are what's called "4M"- they are 4" speakers that don't have a standard mounting pattern. the top of the speaker (closest to the windshield) has standard mounting points. the bottom of the apeaker, however, is where there is non-standard mounting points. crutchfield stated that they recommend the 3.5" speakers, as well, and include a plastic sheet to make your own custom adapter to mount the speaker to the non-standard points. after looking at the 3.5" & 4" speaker options, i've opted to order some 4" sony 2way speakers to try to customize fitting into the dash. i know it's somewhat risky (wasting the money), but i feel it's less customizing than doing the crutchfield method of custom cutting plastic. all i really "should" have to do is cut the bottom tabs off the 4" speaker and the rest "should" fit like a glove. i'll know soon about this.

the rear speakers are more of an issue if you want to retain a stock look. they are 5" speakers which are non-standard these days as well. i'm surprised your speaker shop said they were 5". crutchfield recommended 5.25" speakers and minor cutting of the package shelf to accomodate the extra .25". you can't use the "stock" speaker grills with this method. personally, i want to keep the stock speaker grill look. so, i'm investigating reconing the stock speakers with upgraded speaker materials. i'm in process of investigating this. there is a caveat with this. with reconing you don't get a 2way or 3way speaker; it stays "full range", unless you opt to doing a bit more customization by adding a crossover and a separate tweeter. i'm investigating this as well.

keep in touch with what you find. i'll do the same.

-lance