Guys between the Losi conversion and the RCPD which one?

Also I seen the losi parts sold seperetly somewere but cant remember. Any ideas?

Is it better for balance to have the ESC above the diff instead of behind the battery tray? Like maybe the RCPD kit but with the Losi receiver box?

And will the Neu finned models fit with either motor mount? I heard about someone grinding their motor for some reason.
Guys your help ASAP would be greatly appreciated as I would like to order by sunday night so I can have it at the local track this week.

I been reading anywere from 168-170 for the Losi tray. My battery is going to be either 168 or 157. Thankx

So how big is it really? I been trying to measure it but my calipers only go up to 150