[BaggieMatt]

If you are going for the 6 channel setup (2 x bass, 2 x front door and 2x rear door) I would suggest coding the amp to E87 rather than E60. The E87 has the same setup. If you only use 6 channels and E60 coding then I have found in the past that it is bass heavy as it boosts the bass a bit thinking it has the extra set of mids/tweeters at the rear.

[ccfj1]

I'd be tempted to make and adapter from hifi to top.

I installed EPS (individual) in my e92 (from base) and it was easy enough, it was just more speakers tbh.

an adapter would make it plug and play.

[emhtuning]

I'd be tempted to make and adapter from hifi to top.

I installed EPS (individual) in my e92 (from base) and it was easy enough, it was just more speakers tbh.

an adapter would make it plug and play.

there is a guy called Technic in USA who sells some Plug and play harness to add aftermarket subwoofers for HIFI and TOP HIFI amplifiers.

I tried to convince him to make HIFI to TOP HIFI harness but he showed no interest , maybe he thought there is no business for that .

I tried to do it which is an easy job but I was not able to secure the male connector showing the picture below .

if anyone knows anyone part number of this connector or the source online then the rest is easy.