Probably not. What head unit are you planning on getting?
What you should do is power the dash and door speakers directly off of the new receiver/HU because it will most likely be more powerful than that old OEM amp (not sure what you have). It doesn't make sense to drop the output then amplify it again unless your amp puts out more than 40-50 watts per channel RMS, which is what most HUs put out these days.
My sound improved dratically by running my infinity dash and door speakers straight off of the HU. Louder and clearer.
My 250 watt amp is for the 8" Kicker sub only (most HUs come with subwoofer pre-amp line outs so no line drop needed there).