MB Quart 5.25" Will they fit ?

Yes they fit. Actually you could fit 6.5s I have that same model of MB quart 6.5s in my Tc. Yes they do mean 6 speakers including tweets.

Finally you don't have to have alpman's tweets but they help.

You mean adapters right ?

They don't sit too deep in the door?
Worried about mosture.

i have the mb quart pce 216 6.5 front and rear. fit great with a good shop install.......

p series is the premium series. the d or discus series you have were actually made by rockford fosgate. that sux... they are still excellent speakers.. better than any best buy brand ... but you got to go to the p series for them to still be hand made in germany. how much did you pay??? did you check ebay?? i ebayed minme and got the for 200 a pair when at my local shop they are 550 a pair!!!!

Yes, you will need to either make adapters or buy alpmans, with the adapters i got 6 3/4" in the front doors and 6 1/2" in the rear panels. They keep the speaker out far enough so it doesn't interfere with the window.