01 740i - Are upgrades to Bluetooth possible

can an 01 740i Sport be changed?

obviously the inbuilt fone system is obsolete tho the idea of answerng and using the inbuilt mike and speaker system intrigues.

the NAV was fried (i guess thats an MK ii) and am considering upgrading to MK iv based on posts.
but while we are at it, any merit to pulling the entire display screen etc in favor of newer bells and whistles?

Radio still works btw., but of course shuts off after a few minutes due toNAV computer needing replacement.

any idea what caused it. most of the time its due to inproper battery charging. from what most people say anyways.